But I will answer your main questions since your comment seems to be in good faith.
Just like angular 1 choked on complex, high-frequency UIs, HTMX is going to follow the same faith. Github uses a similar approach to HTMX and you will find that even for such a simple system, their notification indicator elements on the same page are often out of sync.
The reasons for this is that State Management is hard, which is why the reconciliation loop of React-like frameworks and shadow-dom does away with pushing complex state management to user application and handles it systematically.
Of course, this doesn't mean htmx is useless, for a specific case of web apps, it is good enough, but the problem is that often times, you start with "specific cases" and your application grows overtime.
So when you consider that and the cost of doing htmx vs React or any react-like framework, picking htmx is only reasonable if it is the only option you're comfortable with and rarely on merit.