They keep doing patches, reworks, and skill adjustments just for these classes to cope with the current meta. Pearl Abyss just loves its original class roster.
Also, it is a no-brainer that the Warrior is on this list because, like the Berserker, these two are the pioneer class for BDO.
Harnessing both the standard weapons for a knight, the Warrior class of Black Desert Online defines the knight for its game. Just the straightforward concept of a 'knight,' vesting a full-plated armor and going with either a sword and shield or the more fabulous type, an enormous two-handed greatsword.