[jasonmorton]

I've been using emacs for many years now, and I'm sad to say that it has never been slower, despite the hardware getting better. Now it lags like crazy when editing a latex document, no matter the recent version. Something went off the rails in the last year or so, and even Atom is more responsive.

[tikhonj]

Have you tried the new native compilation system? I haven't worked on LaTeX documents specifically, but I did see a noticeable improvement in responsiveness across the board and a massive improvement in Elisp-heavy functionality like org-agenda.

I've used it on both Linux and macOS; for whatever reason, my Emacs has always been snappier on my Linux machine, and that's still true with native compilation, but now the macOS experience is also pretty solid.

[BeetleB]

Have you tried profiling? It's working fine with me on both Windows (without WSL) and Linux.

[unhammer]

Even without your init file (`emacs -Q`)? Or try profiling (M-x profiler-start, pick cpu, do stuff, then M-x profiler-report) to see if any third party package is involved or not