What should a native DOM templating API look like?

I think I've cracked this [1]. A lot of the popular frameworks just copy each other by using funky attributes, templating hacks, and compilers. You don't need that (yes, they have certain positives and negatives but you don't need them).

Instead, what's hinted at in this article (using a plain HTML string) works great. Add in a little abstraction for the sake of structure and simplicity and you've got a surprisingly robust UI framework without a ton of complexity.

[1] https://cheatcode.co/joystick (a full-stack JS framework that has its own components API)

At a glance, this seems like a clone of React with react-router v6. How is it different?

Not really like React at all (and certainly not React Router). Not sure how you made that connection...

The component method in the framework is inspired by React v1 (really just that it's a function you call—my approach to everything else is different), but all of the routing is on the server-side (a light abstraction that maps back to Express.js routes).

Maybe it was the lifecycle hooks. :)

If you're going to evaluate a piece of technology at least take the time to play with it. This isn't just unhelpful to me, it's doing a disservice to yourself (assuming that I've created something that will help you and improve how you do your work).