I would never want to write template files in something other than JSX at this point. Every library that does binding via HTML attributes is a huge step back, as far as I'm concerned.
I'd also say React's one way data binding was a big step forward when it was released. Where it (and TBH, many other SPA frameworks at the time) missed the boat was form handling, which it turns out is like 90% of the Internet and internal applications.
I wouldn't say it's 90% (although my last quibble regarding percentages in this very thread got downvoted to 0) but it is tedious and sort of difficult because of the tediousness, but not sure I have ever seen any solution for forms that made me say, damn I like working with this.