What I'm seeing is (assuming a half decent Session 0) a selfish player and a matter of bad design. "The DM made an underdark campaign but I chose Tundra and the DM won't move the campaign hundreds of miles. Waaaahhhh! Why doesn't the entire campaign revolve around MEEEEEEE!!!" And yes that is bad.
Why are you assuming any of that? The DM at the session 0 should decide with the players what their adventure will be. If it's a prewritten adventure, the players should make their characters based on that. If it's a homebrew adventure, the players should make their characters first and then the DM should design the adventure around that. If a player's backstory says that they're the secret child of a monarch, the DM should keep that in mind when coming up with an adventure for the party to do.
If a player chooses to make an Aarakocra in this scenario, in order to properly challenge that player, the DM is going to have to alter the adventure to add more ranged/flying enemies. That's not a "Waaaah, why doesn't the campaign revolve around me", that's a "hey, can you keep in mind that this is what my character is like when making the adventure/encounters?"
What's particularly bad is that this is the fault of the designers. What should happen is that favoured terrain should give you bonuses anywhere certain situations arise that are most common in those terrains rather than being as useful as a chocolate teapot outside specific terrains. For example if Tundra gave you Cold Resistance anywhere (because Tundras are cold) it would be comparatively easy to work that in and is likely to come up naturally. So there would have been no problem.
I actually agree with you that WotC should have designed Favored Enemy and Natural Explorer like that. But they didn't. So the issue about how to be a good DM in this scenario comes up.
This isn't about being "anti-player". You aren't specifically targeting anything the players are doing. This is about being anti-DM and giving the DM extra things that they have to do that there's no benefit for them for doing and that doesn't make the adventure any more inherently interesting.
A failure to communicate when it could significantly affect the effectiveness of a character is being anti-player.
This is complete nonsense. There is an entire effective school of DMing where the DM is intended to be neutral because the fundamental fantasy is overcoming the world and the challenges it throws at you, not having the world tailor made to your whims. Calling basically the entire OSR badwrongfun is a problem.
You can challenge the players without ignoring their character decisions. And you somehow took my "don't be actively hostile with the players" as an attack on neutral DMs and the OSR.
And the players' character choices should be designed with the campaign in mind. And the designers should make sure that additional makework isn't loaded onto the DM just because they thought some half-assed idea was cool. This is a matter of loading something onto the DM that isn't necessary.
That entirely depends on if the adventure is pre-written or if the DM is making the adventure. If the adventure is pre-written, then the players should design characters around that. If the DM is making the adventure after the PCs are made, the adventure should be designed around that. And if the DM is involved in the creation of the characters, then the adventure is easier to design and the DM is able to squash any parts of the character that they feel might be unacceptable for the campaign.
And if the ranger chooses Undead knowing it's a pre-written adventure that's on them. As for letting people participate underwater that's a default thing and any DM who creates an adventure not expecting that the players will need help with that are fools.
Again, why are you assuming a pre-written adventure? And the underwater adventure thing was exactly my point. Saying "player choices be damned, this adventure takes place in the Elemental Plane of Water" without making sure all of the PCs can breathe underwater or giving them a magic item/spell that lets them do that is bad DMing. I was using a reductio ad absurdum argument on the "the world/adventure shouldn't change based on the characters" argument that
@Micah Sweet was making.
Meanwhile the player's job is also to make the game fun for everyone. And they know the DM already puts in three times as much work as they do at the bare minimum. If players are making choices that can only come up if the DM decides to rewrite significant parts of the adventure to cater to them (something that will make the DM's job harder and less fun) they are making things less fun. And that's on them.
So, you're agreeing that both DMs and players should do at least the bare minimum amount of communication required to make sure things go smoothly at the table. "Screw the DM, I'm playing Ultron in Dark Sun" and "Screw the Locathah PC, this adventure will immediately send them to a desert" are both toxic and bad ways to play.
The designer's job is to create a system that engages everyone for minimum effort - and they failed badly here by putting in choices that will make things either less fun for the player who takes them or harder and less fun for the DM.
I agree that the game designers failed when designing Natural Explorer/Favored Enemy.
No it's not - unless you think that the amount of work put into a campaign by the DM and by the players is the same. And unless you think the amount of work to tweak a single character is as much as that to change an entire setting that character is supposed to be from.
Do you genuinely think that the amount of work put in by the DM and the individual players is the same? And happens at the same time?
And if one person is putting in e.g. three times the work as the rest are why do you think giving them the extra work is the same thing?
Where did I ever say that this was all on the DM? I never suggested that the DM had to be the slaves of the players. Just that they should be considerate of the player choices and design the game to be more fun for them.