You're contradicting yourself.

"...and you never really need to worry about it."

If you never need to worry about it, what's the point of having it there in the first place?

"...making hunter pets less interesting."

How is it more interesting to never have to worry about happiness because it just gets taken care of than to never have to worry about happiness because it's no longer a game mechanic? It was somehow more interesting to ignore it because your skills and/or glyphs took care of it than to ignore it because the mechanic is gone?

"So, I don't really think it counts as a quality of life change - there is no hardship to improve."

Precisely. It changes nothing. Because of this, it's just wasted code in the program, complicating the code to add a system, and then complicating it further to make sure the player never has to deal with it. If the goal is to make sure the player never has to deal with it, then just rip it out. If you want it to actually be "interesting", remove the glyph and the skills that make it so you never have to deal with it. But keeping it as it is now makes no sense.