I believe that the comparison with the "de facto" standard Industrial SanDisk card is the benchmark. That is why I've included it.
I did not mention on the card benchmark, but the MacBook Pro card reader is attached to the PCI interface so it is as fast as you can get, and the cards performance are really what is being measured.
I got very similar results, with a very fancy USB3 card reader from Sandisk while connected to a Windows PC, copying several videos (4GB each) to and from the internal SSD drive.
Yes, I've left the Anafi recording 4k video for over an hour (landed of course 
)
And regarding 2) I really don't think 100M cards are required....but YMMV
