SafetyNet itself is obsolete, but the microG toggle to enable it does other things too to help attempt to pass integrity checks. “(Google” Play Integrity" is what newer apps will interrogate, and there are 3 levels, of which microG based devices will only pass the first level “basic integrity”. They more advanced level integrity checks aren’t yet able to be gotten around.
I am not an authority, but I personally don’t know that a locked / unlocked bootloader makes a difference in passing various checks under iodé as these checks are blocked?