I have heard this but been unable to test it as I use a Samsung and a non-default Gallery app. BUT.
Apparently on iOS if you use the draw tool and draw a circle, square, diamond or other simple shape, you can hold on the final point and the app will clean up the lines and make them straight/symmetrical/properly curved.
If you didn't set those up yourself it might be a model thing to have those by default. On my Moto G 5G the power button thing isn't bound by default. Though the volume button media thing is set for when the screen is off. There's a section in the settings for gestures with all of them.
Options for my model at least have a couple cool "kinetic gestures" as they call them. If you hold the phone in one hand and make 2 quick chopping motions it'll turn on the flashlight, if you instead twist your wrist back and forth twice quickly that'll open up the camera. Both work even if the phone is locked.
I am not sure what extra phone features my phone has that I don't know about. But I think, yes, the notification curation feature and also the SOS feature that these comments section mentioned. However, I want to tell you what came to my mind just now. It's called "Personal Safety" on Android devices. These can be applied before entering situations like these: if we are going to a place we suspect is dangerous, we can turn on the active Personal Safety feature. The recipient notifications will ring if the participant's phone has low battery, low signal, or if the SOS button is turned on, or I can't remember the others because I haven't discovered it fully yet. Let us know if you guys understand the idea of it.