i find it so much harder to grok the structure of Vue 3.x code. A data variable or prop can be defined literally anywhere. And it could be directly reactive or a ref. It's all cognitive load I didn't need before. Vue was always "worse" than react in both mind share and flexibility / purity and power. But it made up for all of it with the beautiful intuitive simplicity. So much of that is lost but I find it hard to argue any of the other aspects are better than React now. So Vue just feels overall a bit mediocre now.
I will say, with 2.x about 50% of bugs where not using Vue.set(...) in some obscure place or way, and those have all gone away, which I love.
We're currently going through a migration of writing new components in composition style, but obviously have a lot of experience with the options API and a lot of existing code using it.
It's taken the team some time to get used to how to do things in the new way, but on balance, we do like it.
It feels like there have been some odd caveats, like the new reactivity system approach not working exactly like we'd expect. But caveats exist in the options API too.
I will say, with 2.x about 50% of bugs where not using Vue.set(...) in some obscure place or way, and those have all gone away, which I love.