Use a second computer or a friend’s one to download the updates, get a USB ethernet adapter (a 100mbps one is like $5), put the system drive in a computer with lan, tether with another device via USB (phone, pi zero, etc) or use a different version/distro. I’m sure there are a bunch of other solutions.
Raspberry, seriously? What problems are you seeing?
I have a raspberry pi 3 acting as a 5GHz access point for as long as it’s been on the market, I can remember one time I had to restart it because of some wonkiness. About a dozen others as clients, never had an issue there either, fast and stable enough.
All using the default os (raspbian first, raspberry os later).