Earlier quoted context omitted.
Trying to put it politely, but your question seems a bit confused. Arch is not the only distro that strives for minimal modifications on upstream packages. In fact, most distributions work that way - it's Debian and its derivatives that's the outlier, and these days, even Debian rarely patches upstream packages. There is much more to distributions than what patches they apply to their packages. The package manger the…
Thanks for explaining. I'm (obviously, I thought) not suggesting distros are only about the patches, but patches are a very significant aspect of their raisons d'être to me. I thought most distro maintainers do things like backporting changes though, for security/stability/etc.? Including RedHat, Canonical, the Debian maintainers, etc.? Arch (and I guess Gentoo, and maybe their derivatives like Manjaro) are the only…
Ubuntu is a Debian derivative, they patch things heavily, just like Debian.
SUSE, I don't know about their policy. I assume they're like RHEL, which starts from Fedora, which is close to upstream, and then backports bugfixes from later versions on to stable branches.
Many distros maintain stable branches and just update the packages on that branch when they have security issues. Backporting security fixes has (somewhat) gone out of favor, because backports executed by package maintainers that weren't familiar with the code have caused serious security issues in the past. Of course, distros like RHEL and (I guess) SUSE still do backport security fixes to their stable branches. But they start from a base which is close to upstream - it just diverges more and more as their stable branch gets older and older.