this reference from our ICT department worked for me: leave everything as-is for ubuntu 22.04 OS, but tell wpa-supplicant (specifically) to work with a 'less strict' version:
How to connect to WPA2/PEAP/MSCHAPv2 enterprise wifi networks that don't use a CA_Certificate, like Eduroam
I rebooted and I then had to 'edit' the eduroam entry inside wifi settings, because the settings somehow now contained 'ca.pem' as a certificate, while you should (as far as I know) select 'no CA certificate needed' for eduroam.
So after selecting 'no certificated needed', my laptop connects to eduroam again.
btw: the ethernet at our university also didn't work anymore after the upgrade to 22.04; also this is repaired now for me (probably wpa-supplicant is used for both wifi as well as ethernet?).