[ultimafan]

I think both can be true and that seems to track with what you are saying- modern DMs being expected to do much more and overperform in some areas (theatrics, atmosphere, narrative, game/combat balance, make sure players are having "fun" and are being challenged but not too much so) and at the same time are expected to do much less in others (like knowing/refereeing the rules like the back of their hand, being the final arbitrator and having the final and often only say in a ruling). I've definitely noticed the same. And noticed how in some cases the modern approach has "bled back" so to speak and a group I played 1E both before and after 3E/4E/5E, had a completely different expectation of the older game when we returned to it out of nostalgia.

This next part is also purely anecdotal, but something I've observed in several groups so I think it's interesting to note- playing in groups of mostly pre-3E players, I hardly ever see arguments with the DM break out over rules/rulings, both then and now. But playing 3E/5E, or playing other games with people who primarily play 3E/5E, there are many occasions where the flow of the game is interrupted for quite long arguments between player and DM because a player is not satisfied with some resolution or not being allowed to do/play as something in particular and thinks the DM should do it a different way. It feels like there's a much bigger cultural expectation that the DM is there to entertain and enable the players fantasy and not to be an impartial judge for a world the players are exploring. But like all things I'm sure people can chime in with completely different experiences for all the editions