pCloud rate limit
I use pCloud as my utility cloud service provider. It’s pretty good.
But boy was I surprised when urgently uploading a 3 GB video file to see transfer rates of 60 or 80 kB/s! Turns out that the pCloud macOS client has rate limiting, where the default Auto setting achieves numbers like that. Access Settings > Speed, Upload Speed Limit, and click Unlimited. Saved my day.