Long story short, but I learned last week (and a couple of years or so after the fact) that the openSSH team have advised people to move away from scp (secure copy) towards SFTP (SSH/Secure file transfer protocol) and rsync.
sftp should also not be confused with ftps - that’s completely different, and not secure.
I’ve used scp a little over the last few years, mainly for one-off copies between my Ubuntu server and a couple of Pis I have, but any normal file copy I do I’ve long used rsync (or Robocopy sometimes from the Windows box). sftp is quite nice to use, allowing simple local and remove directory traversal so it’s certainly a more usable option too!
Anyway, I was a little surprised it’s been formally deprecated in many enterprise distros too, and the reasons are solid - it’s old, isn’t regularly maintained, has some structural security questions and a few recent CVEs.
So goodbye scp!