I’m not an electrician so I really can’t say with full confidence.

I’m not sure what the backstabbing comment has to do with the WAGOs. The ones usually recommended by the internet are the 221s which are never nuts. No backstabbing with those. Are you referring to specific receptacles? I don’t backstab with those either. I’ll side wire or J-hook then if side wiring isn’t available.

I’ve seen some videos of people satisfied with products like the WAGO 773 but I don’t have experience with them.

I don’t think there’s an issue if wires are snug. As long as they fit in the box it should be fine.

The purpose of electrical tape is basically done insurance to make sure nothing touches the wires accidentally. It does basically nothing for mechanical support.