I don't want to roleplay as evil but less of a holier than thou asshole 🤣
Reading the paladin dialogue... they are just so obnoxious
Paladins have always been that way

In the original D&D rules Paladins could only be Lawful/Good and follow appropriate divinities. There was no moral greyness, you lost your divine powers if you strayed from L/G in your actions, unless you performed atonement specified by your deity.
For evil deities like Lolth, there was an alternative class called the Blackguard that had similar divine powers, but oriented towards Chaotic/Evil. Blackguards seem to have disappeared in official 5e, so I guess oathbreaker is as near to Blackguard as you will get in BG3.
Although, I notice that patch 9 notes say that Minthara is now a Paladin, and she is from Lolth-loving Menzoberranzan, which seems to not fit the 5e class definition

So who knows what will be available when the game releases.