I don't think the majority of people like to pick classes because they are the strongest, unless they want to beat a challenging mode and get the trophy or whatever. I think the motiviation lies more in coming up or optimizing a concept than actually playing it. You see so many people on the bg3builds reddit, that bascially just theorycraft without actually having played the build.
Many of these BG3 powerbuilds take ages to unlock. Many have lots of empty levels before you get all the abilities, or it takes a long time until you have all the gear needed.
The core of the new dvinity will propably still be an rpg. I think a lot of people me included sometimes make the mistake of seeing it as a roguelike where you basically can try out your desired build within a few hours. Would love a roguelike of bg3 or the new divnity but realistically it is still an rpg, which have a slow progression.
Additionally we still see in D&D5 that spellcasters are much more fun, have much more options, than non-spellcasters. Not as strongly as with previous editions, but its still very much there.
I never had an issue playing DnD with friends but playing the DnD system in a videogame kind of sucked in terms of balancing. Every spellcaster feels super weak in act 1, because they don't have a lot of resources in order to cast spells and actually feel impactful. Where as martials don't have a resource at all and feel strong right from the get go. I takes way to long till spellcaster start to feel good. I'm actually glad we have schools in divinity rather than one type of character has to rely on a resource and the other doesn't.
I also like the cooldown system a lot more in divinity than the DnD system in BG3. There you would do the same gameplay loop every turn. For Martials thats usually something like booming blade into extra attack or throw weapon into another throw weapon and that every single turn. That is boring as hell. With cooldowns at least you cant just spam the same action/ability every single round.
