Dark Souls 3 Proof That Armor Does Not Matter (Tutorial Optional Boss)

This is optional boss in tutorial area. I read that easy way to kill it is to try to make him follow and drop him off the cliff. I also read that Knight is by far best starting class because it has one of best armor sets in entire game which rest of starting options will not see until late game. I admit I am total newbie to Dark Souls series, but I really did not expect "one of best armor sets" to be this effective. The only possible conclusion is that armor is entirely irrelevant in this game as only challenge are bosses and PVP. Currently PVP is dominated by bleed and greatshields and being quick and able to roll out of the way is the ONLY way to survive long enough to win.