You don't even need an adapter, anyone can get a cheap hid controller and play. What pisses me off is that attitude anti wired controllers, go use Devo if you want wireless right now.
Our whole life we had wired controllers and now suddenly it's blasphemy, where does this people come from? It limits where you can sit and stuff but you won't die for using it.
To me compatibility goes first because anything else are just details or alternatives to something that is already there (wireless instead of wired, real mc because lazy to transfer saves, etc) and it's a minority who ask for that. If you want it so bad, code it yourself.