> specialized hosting

What do you mean?

My private next.js fullstack slop runs dockerized on my kubernetes cluster and for auth I use auth0, because I am too lazy to run keycloak or whatever dockerized auth slop is currently en vogue.

It's possible but most default to vercel and it's required if you want the fancy stuff (hybrid). And you made my point, Kubernetes is overkill as well.

Regarding auth, in phoenix it's literally as simple as "mix phx.gen.auth Accounts User users" and boom, your users live right in your database for free.