> SFTP is an encrypted protocol, so maybe those CPU cycles add up to a lot of extra work over time or slowdown. That… shouldn’t feel convincing to anyone who gives it more than 15 seconds of thought, but we all live with our eyes wide shut at times.

FWIW, I previously spent some time trying to get the maximum possible throughput when copying files between a Windows host and a Linux VM, and the encryption used by most protocols did actually become a bottleneck eventually. I expect this isn't a big factor on 1gbps ethernet, but I've never measured it.