The /etc/nsswitch.conf file has been moved to /etc/authselect/nsswitch.conf and linked back to /etc/nsswitch.conf. Need that updated.
sssd v2 recommends switching the lookup so the sss is searched first because of changes made to the sssd module which make it much quicker than nss reading the files.
Note this is a secondary module not a SIMP module. There appears to already be a request out for EL8 updates. Make sure that works and if so second it to see if it gets pushed through.