I'm not an expert on these devices, but I don't expect many would exceed 4K requirements these days. I have never come across media that is beyond 4K so I see little need to chase specifications beyond those levels. I'm not saying those devices don't exist, it's just I haven't seen a need for them so I haven't chased them down. I see wireless as a convenience, and not the ultimate way to send data at all times. Hard Wiring is still my preference but sometime the physical situation makes it impractical.
In your case if your current needs are for 4K, by the time your equipment can send and display 8K, a more up to date wireless solution should be available. As per
@TLS Guy , if you decide to go to cabling of any kind, put it in conduit if you are going to live in that place long term.
Just trying to be helpful.