in pathfinder wrath of the righteous.. game was designed with 6 party characters. there seems to be people who played with 4 too and even solo. it's doable. but i won't be punishing myself nor am i having the guts to play the game solo. i'm having a tough challenge even with 6. there are alot of options in regards to the difficulty. like more enemies, enemies with scaled stats and enemies that behave differently as well like.. marking your squishies as sworn enemies.
since pathfinder can implement it, i believe larian can too. the question is only whether if they want to. bg3 has a AAA budget for an RPG while pathfinder wrath came from a small indie studio with no huge budgets. while bg3 looks very appealing visually, the core of the game is still the combat. so i hope larian would give us the options for 6 and customized difficulty options for people who wants to play the way they like to play it.