Level 39
Jetstream like Breeze is not a package but a starter bit, means it makes changes in your framework and these changes are linked to the framework version you use. So, don't say it's impossible to use Vue2 with Laravel9 / Jetstream but it should be difficult to change everything, you can try by making a diff between a laravel install with and witout jetsream.
That said, I should install Laravel8 that used Vue 2.