There's no point "getting into" MvC2 (or Third Strike, or T7, SC2, etc) because the "age of discovery" is over - it's just picking one of the best characters and doing the best combos. You will also never "learn" enough to catch up to people who have been playing it for life (aka Justin Wong). It happens really fast with newer games (felt like it was a month into MVC3) and it's a big reason that Fighting Games are getting eclipsed by other PVP games (Hero Shooters, MMO PVP, MOBAs, Tact Shooters, etc) - because there's such a huge learning curve before you can attempt to get to the "good stuff".
Even if a game is solved that generally doesn't completely stop people who were already new and looking to take a look into older games now that we have better resources. Even then some just play up to their skill cap just so they can get by. These older games with newer audiences at this point are novelties rather than something to invest time into being great cause the competitive part of it is already set, though it does have cases of a random straggler jumping in cause they made the game more readily available.
Overall most would just settle for being good enough to be the best in their 50 mile radius or discord group.
The barrier is only as high as you make it and its not as punishing as the slow burn of being out farmed for 30 mins, though admit that its nowhere near as clear of what goes wrong in fgs than other genres.
Fighting games are locked into a very small area with a single objective that never changes and the only real difference between characters is in their specific tool kits in specific interactions (aka Anti Air vs Jump In, how good a character can zone, any "armor", any command throws, neutral range, meter building, etc) and this doesn't change all that much between generations of fighting games or even different fighting games entirely. Nearly every game is "Win Neutral -> Apply Pressure on Offence -> Do Combo/Spend Meter -> Repeat from Oki" for the attacker and "Take Damage -> Hope you guess correctly -> If you guess correct, see chart #1". Which isn't something you can really balance patch out - it's coded into the very soul of the game.
Thats the niche of fgs. While its not much too different unless you stretch your definition of what a fg could be, it boils down to the standard pvp experience of applying pressure, its just not many ways you can do though this simplistic approach fits the 1v1 setting. Some games that are more "honorary" fgs like Lethal League Blaze or Windjammers which have their own cult following has alternative approaches to this concept, but its very limited ways to approach the objective of beating someone's ass when its no other things to control outside of positioning.
Thats one point where smash overtakes standard fgs cause its more emphasis on stage control both on offense and defense.
I'm not sure how to fix it either - but moving away from "esports" design and back to "core" design (more/better defensive options, more dynamic strategies, less forced "comeback" mechanics, less adherence to poorly realized mechanics [like Kara throws, 1-frame links, etc] and some actual experimental game design) would go a very long way in trying to breathe life into what I consider to be a very dead genre.
Only way to fix something like this is for the community as a whole to accept other styles of play and games being made to be less centered on the system mechanics than the characters themselves. The current design of fighting games are less for the players and more for the audience since they're much more explosive allowing the mentioned artificial comebacks. Defensive play always was the anti hype part of fgs like turtling with the life lead or being an oppressive zoner in general (Ex: JP in sf6 for a time) though right now the current landscape of fgs went too hard on the offense, but it was bound to happen since even 10 years back meter, combo extension, safe pressure, guard crushes and so on got more prominent.
Normally would say this is mostly an American thing since this region is more known for its bulldogging style of play and our choices of games being as aggressive as they are, but playing snk games for the last few years its in those too (2b > max mode cancel). Its just giving the people what they want across the board.
To end this rambling think the less is more approach does more for FGs than combos do. Recently played SC2 again after understanding fgs more and even as a game with a lot under the hood it feels good to play while not being overwhelming or having unnecessary mechanics. Just strong characters that hit hard and are distinctive.