I think it's dangerous to balance around the very few that know the ins and outs of abusing a system and then say "omg, this is so easy". The vast majority of players do NOT abuse those systems, or even know how to abuse them. Wrath of the Righteous on core difficulty is a perfect example of it. Hell, even on normal, it assumes that you know a lot of the rules and are able to abuse a lot of the mechanics. I love wotr, but I don't want to see BG3 go that way.
Using smite on every attack is very natural though. No need to know anything. Just click yes every time when you want to level a boss before they get a turn. 5e is not a perfect system and there is no DM in BG3 to protect the PC's from silly party wipes.
And stuff like this works both ways. Gith patrol with Extra Attacks and Action Surges can easily take down PC's before you get a turn. That is definitely not good game design, going down before you get to do anything. In fact it's not even combat, it's an execution. By level appropriate enemies.
