Yep, the story would be too epic if we get into level 20 cap. The Pathfinder CRPG games go up to level 20 and at the endgame you're practically fighting one of the pantheons.
In Pathfinder: Wrath of the Righteous, you fight baphomet, kill the locus god Deskari, defeat Mephistopheles and kill the daemon lord Nahyndri. You can also reach level 40 if you go the legend path. You're a walking deity at that point.
I would love for Larian to make an attempt for a campaign reaching level 20. It's perfectly doable, just don't implement spells like wish. They skipped dispel magic after all, no reason they can't skip other spells too.
It's not just a matter of spells. It's a matter of where and why you fight. It's a different kind of story. Baldur's gate is irrelevant in a tier3 or 4 story. It's about the gods and planes. Faerun is a small backyard once you reach these levels.
Where and why isn't exactly a issue though? The writers aren't locked to a specific story as far as I know. Wrath of the righteous is mainly centered around two cities, yet the whole world was at stake and they managed to fit in both gods and daemon lords.
It's all doable, but if Larian wants to do such a story is another one.
And why the fuck would so many gods and demi-gods care about this single city? That feels like these movies where it's all about New-York and nothing else matters.
The question is also about what you want at this point: do you want finely crafted tactical encounters? Or do you want to play demi-gods bringing chaos on the mortal worlds?
Another way to put it is what's the point of tier3 and 4 if you want the same things than tier2 but with bigger numbers?
The universe of dnd has unbounded magic. Myrkul, Baine and Bhaal were mortals who went to a god and took its power. It's hard to account for something like that in an openworld.
Divinity original sin 2 did exactly this, but then 2 things are different : the story was about this right from the start, and the universe doesn't have the kind of magic dnd has.
Finally I think larian talked about it, and they didn't say it was impossible, but that it was a different beast to tackle. They probably would have needed much more time and budget for higher tiers. And probably a different story.
Well that went from 0 to a hundred real quick. I'm not sure why wanting BG3 with a level cap 20 gets your goat like that.
All I was saying is that it's doable and it worked great in pathfinder WotR, and that I would love to see Larian have a crack at it. It's not a diss on BG3 or anything like that.
I don't like DMing when it gets too high. Combat just drags and it becomes harder and harder to figure out what is going on. Level 5 is my favorite, people got some cool stuff but not overwhelming.
Remember that a lot of stuff, especially attacks, are abstracted in the rules. An attack roll isn't necessarily a single swing of a weapon, and a single swing isn't necessarily just one attack roll. It's more of a measure of how effective your attack(s) is/are within a given timeframe.