[insidious]

WOW, macOS looks more complicated than linux, verifying apps? What is that supposed to be doing actually?

It's not really anymore complicated. Linux does this too, except it's been doing it for longer than Mac so they got everything down to a tee.

Verifying an app usually means that you can be sure the app/package you've downloaded is the exact one you'd expect (no MiTM, or other fuckery)

For example, all packages on the Arch Linux User Repo and Official repo are GPG signed, kept up to date with a keyring package that comes with the distro. On arch, though, this mostly happens in the background, and if all your keys are up to date/have all the ones you need you may not even notice it's verifying the packages.