Why stun is a bad fighting game mechanic

I actually can't personally speak on X factor, never played UMVC3 so I actually don't have the right to go there. But stun is by far the worst fighting game mechanic I've ever had the displeasure of being a piss stain on whats a well done fighting game (it took a long time to cook but SFV finally is a good game). I never thought I would hate a fighting game mechanic more than rage (rage is a comeback mechanic in smash4/Ult that makes it to where the more percent you have the more knockback you have. But, on top of the fact that it's a comeback mechanic and it rewards you for losing. It affects BASE knockback in smash4 so auto links that have very specific set knockback values get jacked up through the roof and end up letting you kill people at no joke 0%. It's toned down in ultimate but it's still really lame. In smash 4 it was so bad you pretty much just never had a lead). But fucking shit stun is AWFUL.

First: I wanna debunk the age old argument of "it's good because it rewards you for pushing and being aggressive." There are many counters to this. One is that there shouldn't be a game mechanic that pushes you to play a certain way in a game that boasts about playing the game how you want. If you're opponent's stun bar is pixels away from popping you're straight up objectively playing optimally if you're not trying to go for the pop. This is bad design. I should have the game telling me when I should push and when I should have to back dash my ass off, play defensive as fuck, and burn V meter.

Secondly:  Both objectively in good game design, and subjectively to my personal tastes, there should be NO reward for losing in any competitive game, and there shouldn't be over rewards for winning. I never thought I'd see the day where I would hate a mechanic that over rewards the winner than one that rewards the loser since I'm a huge advocate of the more skilled player coming out on top 100% of the time. Which is why I hate comeback "mechanics." There shouldn't be comeback "mechanics" in a game designed to find out who's the best. Earn that shit your self, you shouldn't have to have the game literally play favorites to someone who doesn't deserve it. But stun is so FUCKING stupid because not only is the game just accepting half the work and then it just gives the rest of it to you, but its fucking dumb as SHIT that someone as fucking buff as ryu or akuma gets their block knocked for a loop by a fucking jab or hip check. At least with shield breaks in smash you have to commit to a charged up smash attack or a shield breaker move that has tons of end lag and/or startup. But in SF you can just jab em and POP, game over. You lose even though you still had HALF you HP left from a FUCKING JAB. Have to say it again, but it's bad game design for you to put in SOME of the work, and then the game does the rest for you.

TLDR: Bad because the game forces you to play a certain way. And bad because its an over reward.