No, humans can dual class which is much better. Want to rule Throne of Bhaal? Build a cleric to level 17, dual class to mage. That build can take on the gods themselves. Want to tell a story about the rogue who went legit? Build a thief to level five and dual class.
Let me explain. You cannot
level 17 cleric and dual to wizard and use both in BG2 without removing the xp cap; via mod, cheat or using console. Highest level u can dual class is 13 regarding XP cap.
Dual classing means u forfeit ur previous class all of its modifiers, proficiencies, abilities "except hitpoints". That class level becomes inactive, untill ur new class gets 1 level higher than the previous one which is 18 in ur case. So dual classing very much at the end game means, good luck using sling untill the end of TB. Carried by the rest of ur party being a hutchback prettymuch. When you hit Lvl 18 wizard u, will have ur cleric abilities and proficiencies back. Again which is totally same with multiclassing in a very handicapped way.
And how does that makes sense, like you dual from fighter Lvl 13 lets say and become a wizard but somehow u forget which end u grab the sword?
for the upcoming 14 Levels..
its pretty broken in an unfixable way since thats a core rule in that edition..But yea back in the day that was the only option to be able to get a prestige/subclass and multi with an other one..Like a kensai/mage. which you can do those kind of levelling choices with out weird rules like they were in 2nd edition, thanks to the laterones.
And about godliness, its pretty much same having a Lvl 17 in one class and 18 Lvl in an other, makes u godlike. Tempus himself is a Lvl 20 warrior + Lvl 20 Barbarian. Most demigods are Lvl 10 +Lvl 20 of an other class.
But again I am not calling all 2nd edition was utterly crappy just outdated as it is..On the other hand tell me that in 2nd edition all weps have different speeds and I would definitely say it was amazing and adds more versality to the gameplay although making it harder in a way