Your position is that you didn't bother to learn to play, and therefore didn't enjoy the game. And that's a completely valid reason for not enjoying a game, it is how I felt about smash bros after all. But equating this to an objetive assessment is ridiculous. Some of the reasons why you think the game is bad, are reasons why think the game is good. This is the definition of a subjetive opinion, which is all you've given us.
For example, you state that the game is bad because it doesn't have a standard block, instead relying on parry. I would be tempted to say that the parry system is one of the reasons the game is good, but then I would be falling into the same pitfalls you did. I _enjoyed_ the parry system, while you _disliked_ it, is a more honest appraisal.
The parry and dodge system in the game does exactly what it's supposed to: allow you to defend against every possible attack in the game, assuming you have learned to use them effectively. Claiming that it's 'broken' or 'nonfunctional' because you haven't learned to use it properly is disingenuous.
There are no "unfair unblockable offscreen attacks", there is only "I failed to keep track of all the enemies, allowed one of them to get out of my field of view, and attack me from there". Positional awareness is not a skill you develop from 2d fighting games, since they feature a single opponent and a fixed camera.
I'm going to close with one of your statements here, because it perfectly summarizes everything:
"Dark Souls being a perfect example (blocking, parrying, dodging all based on stamina) I understood why I would lose a fight and why I would win in that game, unlike MG Rising."
In MG Rising you did not understand why you would lose a fight, and this is a frustrating experience. However, the fault of that lies within you, not the game, because other people did learn the game's systems. In MGR when I lost a fight, I understood why I lost it. Conversely, a friend of mine was playing Dark Souls, and grew increasingly frustrated because he did not comprehend the system, and was frequently defeated with no apparent reason. He was about to drop the game in disgust, until I gave him a few explanations on how to play, after that he started enjoying the game.