Normal people who use Arch don’t bring it up much, because they’re all sick of the memes and are really, REALLY tired of immediately being called rude elitist neckbeard cultists every time they mention it.
The Ubuntu hate is because Canonical has a long history of making weird, controversial decisions that split the Linux community for no good reason.
The problem there is that stable vs unstable distro uses a slightly different meaning of the word stable than you would use to talk about a stable vs unstable system.
In distro speak, a stable distro is one that changes very little over time, and an unstable one is one that changes constantly. That’s sort of tangentially related to reliability, in that if your system is reliable and doesn’t change then it’s likely to stay that way, but it’s not the same thing as reliability.