Have you considered using Firebase? Can it fit your scope?
You can use it for authentication, storage and other stuff.
This way you can delegate the user authentication to it and focus on the business logic of your app.
I can't swear by this but it seems like a thorough tutorial on how to build authentication with React: robinwieruch.de/complete-firebase-...
Thanks for the answer, I've heard of it but wasn't aware of the entire product offer.
This seems like a very good solution to pretty much everything I asked. I'm going to make a couple of "test" projects with it to get to know how it works.
Also grateful for the link you provided, looks like a good starting point.
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