[can3p]

Local state is indeed a problem that's exacerbated by swapping logic. Simple example: you have a form + a collapsible block inside or maybe a dynamic set of inputs (imagine you're adding items to a catalog and you want to allow to submit more than one). If you save the form and simply swap the html the block state will be reset. Ofc you could set the toggle state somewhere to pass it along to the backend, but that's a pain already compared to spa approach where you don't even bother with that since no state is reset.

You could you query string as mentioned in the article, but that's not really convenient when done in a custom way for every single case.

Having said that I think that a way to go could be a community effort to settle on the ways to handle different ui patterns and interactions with some bigger project to serve as a testing ground. And that includes backend part too, we can look at what rails does with turbo

My opinion is that htmx (and similar) approach is different enough to potentially require a different set of ui interactions and it usually hurts when one tries to apply react friendly interactions to it.