Emacs is a single threaded synchronous and blocking UI system. Sometimes when my autocomplete, C++ checking, git checking, auto formating, ... run, the editor freezes, for multiple seconds.
All this stuff runs in the UI thread. Braindamaged.
The other thing that makes emacs slow is remote editing. Emacs TRAMP uses one ssh connection per command. VS Code spawns a remote server and asynchronously updates the remote's state. VS Code remote editing experience is as good as the local one, but emacs experience is supper laggy, recurrent freezes of multiple seconds, etc. Particularly when navigating the filesystem in the remote in any modern emacs way (helm, ido, etc.). Or when auto-save happens and everything blocks for multiple seconds, etc.
---
I don't really care if native compilation makes single threaded code faster, if that single threaded code runs in the UI thread and blocks the editor for 10 seconds. Sure now it maybe blocks for 9 seconds, because you can't do much about those 9 seconds you have to wait for some IO operation to complete. But that still sucks.