[binaryhermit]

How exactly would HTTPS be spied upon on public wifi?

If the access point tried to MitM the connetction without having a root certificate in your OS or browser's certificate store, the browser would loudly complain if the site didn't have HSTS enabled or refuse to connect if it did

I hate to be that guy, but if you install a random root cert, then you kinda deserve it if you get your info stolen.

EDIT: Granted, the IPs you're accessing and DNS requests would be unencrypted (unless you're using DNS over TLS or DoH with a third-party DNS server) Perhaps the hostname you're connecting to as well, not sure exactly sure what the HTTPS handshake looks like.