Petite Vue appears to be dead. ISTM that Evan You saw Alpine, made a quick proof of concept version using Vue, then handed the project off, and it died. Nothing wrong with that! But I don't think it makes sense to use it over Alpine for anything serious.
“petite-vue is indeed intended to fill the gap for progressive enhancement cases where Vue 3 would be too heavy-handed.
It is not abandoned, but rather it is considered "done" because the scope is well defined. I don't think it needs more features (as that would defeat the purpose of being lean and minimal). If you find yourself needing more than what petite-vue provides, you can either go up to Vue proper, or try https://alpinejs.dev/.
That said, I should update the README to indicate this more clearly.”