Should be a bit faster because it only requests a piece of html fragment which then get swapped into the dom instead of reloading the whole page again.
Yes. That's why I specified "simple page loads". If your frameworkless website is slow then the fault doesn't lie with the nature of http or the intrinsic overhead of full page loads. You've got a shitty backend framework, database or network.
https://htmx.org/essays/a-real-world-react-to-htmx-port/
in which improved performance features as a big part of the realized benefit of the conversion
of course, not every application is going to be amenable to a hypermedia-style approach, so your mileage may vary:
https://htmx.org/essays/when-to-use-hypermedia