Finally, time to post. Get ready for stuff you should take with a grain of salt!
Aaaaaanyway, so yeah, MK9 is a more attractive game on the meta side. To me at least.
Yes, it is more imbalanced. Given how people still haven't given up Marvel 3, how Tekken 7 is looking uninteresting to many people, and how people don't give a flying fuck about one of the most balanced FGs we all could be playing (Virtua Fighter 5 FS), I think it's safe to say we need to throw that argument out the window. Cuz at the end of the day, you noops will still pick top tier if you wanna win and you'll still bitch about XYZ character not being good enough.
Could the characters in MK9 carry you? At times, for sure. But not always. Kabal was easily above everyone...the problem is that there was still a ton to take into account with him vs other good players and quite a deal of muscle memory just to use him. It was possible to pocket him, but chances are you weren't going to destroy people because it was a lot of effort to still play him effectively. Kenshi could mop some characters hard, but there were a lot that he couldn't, and I wouldn't dare test the waters vs Cyrax/Smoke players like DJT, Maxter, Noobe, Wafflez, Detroit, xSmokex, etc. Cyrax was only going to carry you if he hit you with a net (or you were Shang...RIP), and vs better players, that was easier said than done, as we saw from poor Maxter. You couldn't 2-week cookie cutter for the most part. For MKX, it's generally the same shit in a way. You don't see anyone but like SonicFox picking up whoever and beating people just because the character is good...so I'm not gonna discredit it on that aspect.
The problem isn't that, though. The problem is the way the games play. MK9 was crude as shit, but things like more reliable anti airs, offense not being so overwhelming for the most part (and defense as well), and even the standard mobility options push the game in a more positive light than MKX (for me and others). The game really pushed the neutral situation, very few things were so + that they jailed you repeatedly or locked you down harshly, 50/50s that were difficult to fuzzy and led to good damage on both ends were a rarity, and the dash didn't hinder footsies due to how good walking was itself, as well as how fast block-backdashing was. Not saying that MKX is entirely that way or that footsies don't exist in the game, but a lot of the issues with design choices in the game are things MK9 actually got right on the flip side. The fact that there are characters that are near impossible to anti air. Run + really long normals in a game with no mobility otherwise and weak backwards movement is really off-putting for many. And the offense can be really coin-flip centric or just outright oppressing. And then character-wise, MKX doesn't feel as interesting on a gameplay scale. The cast is designed for a more offensive game for the most part, and the offense isn't very different for any character. MK9's characters all felt very different and fit into different archetypes altogether for the most part.
MK9 has its fair share of problems, some unfixable without a total rebuilding of the game. Input bug, meter drain, player 1 priority, random advantage, bad online. And a lot of this thread is realistically fueled by nostalgia (given my rose tinted glasses come out with MKA, that's not really the case with me). But what MK9 had as a game was actually really good. Better than MKX to me. If put on equal footing, with fixes done to mechanics and online like MKX has alongside that final patch, MK9 IMO would be the definitive MK game.
That's just me, though, take it with a grain of salt.