Jeremy Crawford has spoken about changes to the way alignment will be referred to in future D&D books. It starts with a reminder that no rule in D&D dictates your alignment.
(Note that in the transcript below, the questions in quotes were his own words but presumably refer to questions he's seen asked previously).
(Note that in the transcript below, the questions in quotes were his own words but presumably refer to questions he's seen asked previously).
Friendly reminder: no rule in D&D mandates your character's alignment, and no class is restricted to certain alignments. You determine your character's moral compass. I see discussions that refer to such rules, yet they don't exist in 5th edition D&D.
Your character's alignment in D&D doesn't prescribe their behavior. Alignment describes inclinations. It's a roleplaying tool, like flaws, bonds, and ideals. If any of those tools don't serve your group's bliss, don't use them. The game's system doesn't rely on those tools.
D&D has general rules and exceptions to those rules. For example, you choose whatever alignment you want for your character at creation (general rule). There are a few magic items and other transformative effects that might affect a character's alignment (exceptions).
Want a benevolent green dragon in your D&D campaign or a sweet werewolf candlemaker? Do it. The rule in the Monster Manual is that the DM determines a monster's alignment. The DM plays that monster. The DM decides who that monster is in play.
Regarding a D&D monster's alignment, here's the general rule from the Monster Manual: "The alignment specified in a monster's stat block is the default. Feel free to depart from it and change a monster's alignment to suit the needs of your campaign."
"What about the Oathbreaker? It says you have to be evil." The Oathbreaker is a paladin subclass (not a class) designed for NPCs. If your DM lets you use it, you're already being experimental, so if you want to play a kindhearted Oathbreaker, follow your bliss!
"Why are player characters punished for changing their alignment?" There is no general system in 5th-edition D&D for changing your alignment and there are no punishments or rewards in the core rules for changing it. You can just change it. Older editions had such rules.
Even though the rules of 5th-edition D&D state that players and DMs determine alignment, the suggested alignments in our books have undeniably caused confusion. That's why future books will ditch such suggestions for player characters and reframe such things for the DM.
"What about the werewolf's curse of lycanthropy? It makes you evil like the werewolf." The DM determines the alignment of the werewolf. For example, the werewolf you face might be a sweetheart. The alignment in a stat block is a suggestion to the DM, nothing more.
"What about demons, devils, and angels in D&D? Their alignments can't change." They can change. The default story makes the mythological assumptions we expect, but the Monster Manual tells the DM to change any monster's alignment without hesitation to serve the campaign.
"You've reminded us that alignment is a suggestion. Does that mean you're not changing anything about D&D peoples after all?" We are working to remove racist tropes from D&D. Alignment is only one part of that work, and alignment will be treated differently in the future.
"Why are you telling us to ignore the alignment rules in D&D?" I'm not. I'm sharing what the alignment rules have been in the Player's Handbook & Monster Manual since 2014. We know that those rules are insufficient and have changes coming in future products.
Your character's alignment in D&D doesn't prescribe their behavior. Alignment describes inclinations. It's a roleplaying tool, like flaws, bonds, and ideals. If any of those tools don't serve your group's bliss, don't use them. The game's system doesn't rely on those tools.
D&D has general rules and exceptions to those rules. For example, you choose whatever alignment you want for your character at creation (general rule). There are a few magic items and other transformative effects that might affect a character's alignment (exceptions).
Want a benevolent green dragon in your D&D campaign or a sweet werewolf candlemaker? Do it. The rule in the Monster Manual is that the DM determines a monster's alignment. The DM plays that monster. The DM decides who that monster is in play.
Regarding a D&D monster's alignment, here's the general rule from the Monster Manual: "The alignment specified in a monster's stat block is the default. Feel free to depart from it and change a monster's alignment to suit the needs of your campaign."
"What about the Oathbreaker? It says you have to be evil." The Oathbreaker is a paladin subclass (not a class) designed for NPCs. If your DM lets you use it, you're already being experimental, so if you want to play a kindhearted Oathbreaker, follow your bliss!
"Why are player characters punished for changing their alignment?" There is no general system in 5th-edition D&D for changing your alignment and there are no punishments or rewards in the core rules for changing it. You can just change it. Older editions had such rules.
Even though the rules of 5th-edition D&D state that players and DMs determine alignment, the suggested alignments in our books have undeniably caused confusion. That's why future books will ditch such suggestions for player characters and reframe such things for the DM.
"What about the werewolf's curse of lycanthropy? It makes you evil like the werewolf." The DM determines the alignment of the werewolf. For example, the werewolf you face might be a sweetheart. The alignment in a stat block is a suggestion to the DM, nothing more.
"What about demons, devils, and angels in D&D? Their alignments can't change." They can change. The default story makes the mythological assumptions we expect, but the Monster Manual tells the DM to change any monster's alignment without hesitation to serve the campaign.
"You've reminded us that alignment is a suggestion. Does that mean you're not changing anything about D&D peoples after all?" We are working to remove racist tropes from D&D. Alignment is only one part of that work, and alignment will be treated differently in the future.
"Why are you telling us to ignore the alignment rules in D&D?" I'm not. I'm sharing what the alignment rules have been in the Player's Handbook & Monster Manual since 2014. We know that those rules are insufficient and have changes coming in future products.
I track alignment (for 45 years now) and it can change over time. I don't penalize that. People some times do things that aren't within their stated alignment. Too much of that and your alignment shifts. The players who need to worry are usually religious characters who may have to "tow the line" on behavior or get excommunicated. I haven't used Paladins in years btw. I have "Templars" whose alignment varies with their religion. Anyway, I try to judge actions, not intent or reason. I have spent quite a bit of time explaining the concept of "necessary evil" and the problems with "revenge" (no matter how justified it seems). Intent and reason are where most problems arise. Some people can always find an excuse reason for their behavior. And some people don't like to be "judged" (even in a game) for their behavior. They tend to be easier about it when they realize they had reasons for their action, their alignment isn't magically shifting (well, not without magic anyway), and usually realize they need to think through their actions. Or think more about their alignment choices. I've had some fairly interesting redemption arcs over the years (and falls as well). 
