Phone searches at the border are allowable (for now), but border agents cannot force you to enter a passcode. If you're traveling, disable Face ID and go back to using a code.
Way more tech tips to protect your privacy at the border in this post: queeradventurers.com/reduce-digit...
queeradventurers.com
Want to Reduce Digital Footprint While Traveling? What to Know now
This reduce digital footprint checklist walks you through how to minimize your personal data and lock down your phone before travel.