@BaronVonGoon Bruh, that was the whole point of my original reply to you.
I said that the current method of disabling crossplay on Xbox isn't adequate, so there basically IS NO OPTION to disable crossplay currently.
There's no mention of it even being possible like there is on PC and PS5. Both of those platforms get prompts when the game is first launched asking if you want to disable it. Xbox doesn't get that, and you have to navigate the convoluted system menu to disable it with no instructions on how or where to go to do so.
That means that if they did just add mkb support, and did nothing else, like you implied is the "only solution," that Xbox players would be even worse off than they are now.