Earlier quoted context omitted.
Sorry for the delay.. I actually couldn't find any official docs on this feature but this thread covers the bases: https://www.tenforums.com/network-sharing/178379-disable-wla... And it appears it may be part of 20h2, not 21h1 update.
Thanks for the link! I'm searching for 'reboot' and 'restart' but I don't see anything mentioned about rebooting -- only a restart of the network service. Are you sure it actually reboots the PC?
No, it restarts the wlan interface, not the entire pc.