ok you totally brushed over the point here...
also not sure how 600k+ times 3 = 3mill but that's besides the point.
the whole point of that video is to show how stupid and overpowered the "comeback" feature that is x-factor is. he did 3 combos in level 3 and killed 3 people. it is a stupid fucking feature due to this comeback feature. this is like nba jam or the AI on super mario kart. they come back for the sake of coming back.
sure x-factor level 3 isnt an instant win button, but it is just a stupid feature that will allow unbelievable comebacks happen. if you think the thought about xfactor being stupid is in the minority in the high level players you are mistaken.
no clue why you brought up like 5 other games that have nothing at all to do w/mvc3. neither mvc1 or mvc2 had any "powerup" to help the loser come back, and sf2 did massive damage w/out any stupid super comeback powerup as well. it was just a much more powerful and faster game back then.
I did 600k x 5 for the possibility of punishing all 5 mistakes.
The "stupidity" of the comeback is on par with the Ultra system in SF4, and it's actually on par in terms of the amount of hate it received at first. Let's take a look at the first "comeback" mechanic in Capcom fighters...
The Super Combos. In many cases, this ability wasn't a comeback mechanic due to a design flaw (which was changed as more games came out)...the person winning was likely to receive the super combo than the loser but it's equally available to the winning and the loser if they whiff special moves and attacks. Very powerful attack and very likely to kill anyone, for the winning player, this is a way to basically shut down the losing player, or the loser might get lucky and win.
If SF3 you have parrying as the "equalizer technique" but there's way too many issues with this one for me to write about so I will skip it. Major gameplay "complaint" is that it makes the fireball spam game useless, and heavily nerfs the anti-air game and makes the air space a viable vector of attack".
Come SF4 and we get Ultras, which is basically a tool for comeback but also resets the pace of the match because the winning player now has to be careful and is likely to die, just because the opponent is bad. You can only get ultra meter by getting hit or using focus absorb.
MvC1 has the Duo Team Attack which is when both characters come out at once and have infinite specials for a short time. This is by far the worse of the mechanics added to a fighter so far. This is what makes GWM and WM team a huge problem same with Venom and Red Venom. Chip damage and infinite comes galore.
MvC2 is more "Execution" heavy (in that you have to spend lots of time in training mode instead of... playing against others), but a lot of stuff you can do makes the game a lot worse in comparison (the balance issues don't make this any better). The "being good" part of MvC2 was "master he basics", "learn how to do and set up one of the slightly difficult 100% loops" and then a lot of the wins are free since 3/4 of the cast is pretty crappy.
The ease of execution and X-factor make MvC3 an easy execution game but this is how it goes:
Both players start with X-Factor.
Both players can use X-Factor to negate the chip damage, and use the speed boost (when it applies) or damage boost.
It can be used offensively and/or defensively.
Available once per game match.
Easily avoidable (for the most part).
Lastly this makes it pretty even for both players since its always the same for the players.
The one thing that is "unbalanced" is that the damage and speed boosts in X-Factor vary per character, and the level 3 duration is way too damn long. Putting that in perspective... it's a hell of a balanced comeback mechanic compared to most others available in the major capcom fighters.
Other games were mentioned because... they have ridiculous mechanics that a lot of people seem to overlook now for whatever reason like if it was the first time that we have ridiculous comeback mechanics.