MacOS Safari - Stream upload time issues

Hello!  I have several teachers that prefer to use Safari on the Macs, but the upload time for their videos is quite long - 45 min for a short video, that takes about 5 min for the Surface tablets the administrators have.

Strangely, if they install Chrome on their Mac, it also takes 5 minutes for the upload.

Why would Safari take so long?

Thank you!