We still have Vue 2 apps running strong. Our experimental stuff is on Vue 3, which is backwards compatible with Vue 2 for the most part if you avoided mixins (which even in the Vue 2 days was the common advice).
People who say stuff like this have obviously never actually used modern day FE frameworks, because they have all been very stable for a long while. Yes, APIs change, but that's not unique to JS/frontend, and also nothing really forces you to update with them unless you really need some shiny new feature, and at least IME Vue 3 has been nothing but gold since we got on it.