You need to share state. You might only store finished loan applications server side, but often it's nice to allow a user to pick up where they left off. Or keep a list of started, not finished applications, to hand over to sales. Etc.
But sure, application state might not go in the same db/schema as completed transactions.
Well, if you want to allow users to resume sessions from desktop on laptop/phone/tablet - you need to store state somewhere else.
But there are different levels of state: completed transactions (application finished and submitted), partial business logic transactions (three out of five steps completed) and "app state" (field 6 of form 4 partially filled in etc).
They can all be kept diffently in sync (in sync, because the browser will keep partial state via native widgets if nothing else). Even w3m keeps track of inputs in forms before submission.
Seems we are having a different discussion now about shared state instead of whether JS is necessary and capable.
Over used. definitely.
Obsolete and to be derided at every turn. absolutely not.
The initial question (how would you create a form for handling creating multiple dependent resources without using js) - is inherently about various types of state - and if/how to share them between the client and the server.
As I mentioned, I think complex business flows like these can be a great reason to go from "web page" to "web app" - precisely because it enables rich, ephemeral client state with (some) business rules close to the client.
But that doesn't mean you can't do powerful things with just html/http and some form of continuations etc on the back-end.
But sure, application state might not go in the same db/schema as completed transactions.