Security: if they leave checksums on their website I don’t see how it’s any more secure

Up to date: I definitely haven’t had this experience. Multiple times on arch I had issues where an outdated repo caused an app to not be able to boot

Convenience: That’s subjective. I’ve never really seen much convenience from an all in one solution for anything. I find it more of a hassle to find the distro specific manager that has a terrible UI rather than just downloading directly off a web page