Don't know the current state of lit-html and similar, but Typescript support was the biggest thing missing for me when I used it several years ago.

In simple scenarios like just dropping it in an html page, codepen, or something like that I really enjoyed it though.

I mean sure, as long as it runs on the server. Personally I feel JSX is way more expressive. The JSX I write runs on server side rendering to HTML. That way there will be no flash of unstyled content, cumulative layout shift, or any other jank. It looks correct even before the javascript has been downloaded, except it isn't interactive yet.