Where's the Brake?

You switched the account to following-only, turned off autoplay, closed the app. Your kid opened it again and the endless feed was right back. That is not your kid's willpower and it is not your parenting; the loop is built to outlast both, and it is tuned to feed them whatever gets the biggest reaction.

This deck is the recognition and the thirty-second test (set the brake, close the app, reopen: did it hold?), plus what to actually ask for. Not a ban, not confiscating the phone: a brake that works, and stays set.