You can get minor protection on any class by just using circle of protection. It also comes with increased stamina regen, and doesn’t apply the minor defile buff to yourself.

Anyone can get this skill quite easily, it doesn’t cost a huge amount of resources, it has no downside, really.

So why on earth would anyone use a two-piece set for a buff you can get by just slotting one skill?

There are better options if you want more survivability. Engine guardian is good, earthgore is good, trollking is ok as well, you could use lord warden, …

There are just several monster sets who serve a similar purpose (tank lives longer), but do a much better job at it.