You’re answer is disingenuous because it portrays the DM as a passive neutral observer/adjudicator. That just isn’t the case. The DM is a writer, storyteller, actor, reactor, tactician, coach and artist (depending on how good your map drawing skills are).
False. The DM is not a writer, and is
not telling a story. If you want to tell a story, then write a novel. Role-playing has
some overlap with improvisational acting, so the DM is an actor in the same way that the players are actors.
Meta gaming is just a jargon way of describing a player using information they wouldn’t have. The DM isn’t a player. As the storyteller/game master/dungeon master they metagame by definition because they are outside the game itself.
Meta-gaming governs the relationship between in-game reality and out-of-game information. If something exists entirely within the game-world, or entirely outside of the game-world, then meta-gaming is the wrong term for it. If anyone makes any decision about what happens in-game, based on information that only exists out-of-game, then they are a meta-gamer.
You can try and divest the element of choice from the way a DM acts and reacts by claiming they should be neutral, but the reality is I think the DM is constantly making decisions about what the party faces on a session by session basis. If you knowingly put players up against things that are irrelevent, or unachievable then your players will get bored.
It's not your job to make sure that everyone is having fun. (Or rather,
saying that is your job would be missing the point.) Your job is to describe the environment, role-play the NPCs, and adjudicate uncertainty in action resolution. If you can do those things well, then the players will have fun (assuming they actually enjoy role-playing games in the first place).
I’ve just finished the first section of Phandelver. I upped the number of foes and made them hobgoblins because the party despite being brand new players could take it. I added a worg because I knew it would engage the Druid player and portrayed it as an abomination. I expanded the scale of the tunnels to allow the drow fighters better darkvision to come in to play.
I guess you missed the memo, but your actions were in clear violation of the rules. Meta-gaming is explicitly illegal in 5E.
In short rather than invalidating the players choices, I made them relevant by incorporating them into the story. I didn’t make it easy the opposite rather - but I did make it bespoke. They seemed to love it. That’s not a 90’s style of playing - that’s a modern approach, that requires a bit more prep and a bit more imagination/judgement.
Their choices are irrelevant because any other option would have been just as useful. You contrived the depth of the tunnels
because the Drow had superior darkvision, which means they would have been just as well off if they
didn't have it. You turned the goblins into hobgoblins
because the party was stronger, which means their strength was entirely irrelevant, since you would have contrived the difficulty
regardless of how strong they were.
I'm going to stop there, because I don't want to sound overly critical. Let it suffice to say that you are making a great number of mistakes which are common to inexperienced DMs, though they
seem well-intentioned. You're not as bad as the old killer DMs who go out of their way to kill PCs because they think it's a competition, at least. Just maybe consider cutting back on the meta-gaming, unless you have a
very good reason. (Good reasons do exist.) If your players are as inexperienced as you appear to be, then you are teaching them very bad habits, which will not serve them well within the greater role-playing community.