Zany and whimsical are not necessarily the benchmarks of an immersive game. What's immersive about a game world without a day/night cycle and no weather? Where there is no true means o measure time even though the main quest is literally a race against time? Where the map is like a railroaded theme park with everything a short walk away? Where magical way portals are liberally scattered around and yet nobody else in the game world seems to use? It's all so incoherent.
I agree on the time issue in BG3, but not that the case is so clear cut as you make it. Some game mechanics are better in the original BG (e.g. time flow), some are worse (e.g. character reactivity or plot flexibility). For example, a big immersion-breaking moments for me was in BG2, when I've realized npcs didn't react to my werewolf-shifted druid. And another one was when my character got killed by Arkanis Gath, simply because I've made a choice which apparently wasn't approved by the writers.
