Probably because the devs understandably can't account for every possible way people might be using it when shipping new features. But in my experience this means k8s is a bag of fiddly bits that requires some serious ops investments to be reliable for anything serious.

With one exception that was rather big change to some low-level stuff, the "remove beta tags" was done with about a year or more of runway for people to upgrade.

And ultimately, it wasn't hard to upgrade, even if you deal with auto-upgrading cluster and forgot about it, because "live" deployments got auto-upgraded - you do need to update your deployment script/whatever though.