I just installed an Amcrest doorbell which took me like 10 minutes. I'm using it with Scrypted to connect it to HomeKit. I didn't install it for security reasons. My old doorbell switch was broken and I figured as long as I needed to replace it, it would be nice to see what the heck my dog is constantly barking about.
If I wanted something for security reasons, I'd indeed use a PoE camera, but it wouldn't be a doorbell cam. There's very few PoE doorbell cameras in any case and they are quite a bit more expensive. And pulling an ethernet cable to the doorbell switch location would be non-trivial.