They’re hoping you click through to their dedicated article about App Lock here. That’s what Android and tech journalism is these days, blatant attempts to get as many clicks as possible.

Basically it’s a way to lock an app behind biometrics so only you can open it. The submitted article is specifically about those apps having their notifications treated as sensitive. That’s literally it. It could’ve been in the original article about App Lock, but y’know - gotta get those clicks.