An important thing to note about fighting games is that if all you have is esports, you better make sure your game is actually good. If the mechanics are not actually fun to engage with, then your game literally appeals to no one.
Do you honestly think a mechanically bloated tag game Skullgirls would have even the small bit of traction it does have if they didn't go for the racy newgrounds smut aesthetic? Imagine if the cast was just make discount X-Men and legally distinct Justice League characters as the main cast with either no story mode or even worse, the story is just an entirely generic parody of a Spider-Man arc set in not-NYC instead of a bunch of whores in skimpy dress having a (semi) original story and setting.
Very few people would get attached that, even less than they already are. And sure, you can say that YOU would play it, and it's probably even true, but you know that the VAST MAJORITY of people would not be NEARLY as interested.
You have every right to dislike casuals, but remember that they're where 90% of the interest and discussion of your game comes from. If you have $10,000,000 to just burn through from your bosses, then go for it. But if you wish to actually make a profit and SUPPORT YOUR COMMUNITY WITH EPSORTS FROM THE MONEY YOU MADE, then you would actually care about appealing to them. If you only appeal to the FGC alone, then the 3000 sales you made will make you little to no profits and then you're going to have to rely entirely on Matcherino donations for the epsorts cup you want to run, which only that group of 3000 is going to watch. If a game was not a success, they would not have pumped money into it for several years. Why do you think that MVCI only had one year of support, while T7, SFV, DBFZ, etc got several years worth? The casuals did not like MVCI, it did not appeal to them, and the FGC echo chamber was not enough to carry a multi million dollar project.
Blizzard pumped millions into Overwatch story trailers for a reason.