Earlier quoted context omitted.
Tramp works a lot more reliably if you customize where Emacs puts your backups and autosaves, such that they're stored locally instead of remotely. The Emacs wiki has details on how to do that: https://www.emacswiki.org/emacs/BackupDirectory
The biggest problem I have with Tramp performance is much deeper, the need to open a new connection for every request - it makes integrating other modes with Tramp much more difficult than I would hope for (e.g. I tried to make kubernetes-mode work over tramp, and it mostly did, but each refresh had to reconnect, which would freeze the whole Emacs GUI for a second or so; thankfully kubel-mode has a more complete impl…
; use ssh instead of scpx mode for tramp
; this should work a lot better with ssh connection sharing
(setq tramp-default-method "ssh")