A few months ago they improved their security somewhat by not letting you disable Play Protect while on the phone: https://9to5google.com/2025/01/29/google-play-protect-calls/
You also can't turn off Play Protect if you've enabled Advanced Protection on your account (which also enforces a range of other security measures) but that's fully opt-in and hasn't even been availble to the wide public for all that long.