If there's a casual play option, who gives a shit? This is where I think most Wi-Fi players are going to end up. Playing with Wi-Fi is going to come with connections that are good, okay, and bad. It's only fighting games that people treat this shit like war crimes with how Gamer Moment people act about it. If the answer to this is "well Wi-Fi will impact competitive play" then why shouldn't the developer design safety nets for players who lose to noticeably poor connections with matches if people are this offended at the idea of people playing with Wi-Fi? You play against the meme of all Wi-Fi warriors, a Brazilian KoF player, maybe if the connection is so substandard the wins/losses don't tally up in either direction for the match, or if they do ranking can't go down. Filtering out Wi-Fi users won't handle people who yank the cable out. You get what you should expect: not a big deal. People not going "in" on the ideal fighting game experience are not looking to play the game as seriously as those who do. Should be what you expect anyway on such connections.
I have Wi-Fi. I don't care one way or another if people want to play with me. Diehards have actual opponents to get sweaty over, not me. I'm not playing this seriously, nor do I have the resources to address this at present on my end. I'll probably drop the game in a month. But I'm already anticipating my experience to be on the unserious side because I know how toxic this is. Just look at this thread. Look at how people treat fighting games online. It's the worst shit. You can't expect a game aimed for the mass market to "purge" what the audience is most likely to use, and that's not a wired connection. Next to Smash Bros, this is probably the first game since 2008 where you could easily anticipate a mass market audience and not just diehards. It's free real estate for the diehards to maul new players. The ones who will be on wired a year, two, three years down the line will not be the casual audience this game is aimed for. You'll eventually get your "purge" so I don't see what the warring is about. People who dabble with the "Wi-Fi warriors" will either scoff at the mere idea, or give it a try and see what happens. All an indicator doing is letting you know if you're in for a good time, or a time to really not take the game seriously and accept the breakdown. People who don't want to, won't. That's it. Not a big deal.