blaze drops the most per mob (10)
but you dont necessarily want the most exp per mob
because for example blaze takes 2 or 3 or 4 or more hits to kill which really slows you down
mobs like spiders (5+1 to 3) can easily be killed in one hit (bane 5+, str 2, netherite) which increases the exp in the amount of time you spend
however
some game modes dont have spider spawners (olympus) so you may want to use chickens which can also be 1 hit