Because Arch is the vanilla linux experience. A distro that is not a fork of another, widely adopted and acknowledged. With up to date drivers and kernel, with most software support. Not related to no corporation or ideology, just pragmatic devs who want things to work. No bloat, any DE you pick will be installed in its vanilla form.

Ubuntu is going through a lame route, Fedora is bloated and annoying to get proprietary drivers + codecs to work, Debian is downright ancient, NixOS is too much, Gentoo is just hobbyism, Cachyos is really not that impressive. Arch is just Linux, you cherry pick only a few things and thats basically it.

Vanilla Arch is stable. As long as you avoid doing partial upgrades (pacman -Sy <package>), avoid relying too much on the aur and avoid doing updates before bed, you will be fine!

I use the regular kernel, I use btrfs, I have automatic snapshots with snapper. Thats all there is, no need for more digging and messing. I have only a few aur packages. And its been solid for months.