Is Google Drive using QUIC? If so, then its using the same BBR congestion algorithm as the bbr tcp stack, and BBR's algorithm which does not view loss as congestion will help a lot.
It would be interesting to re-try the experiment on Linux or FreeBSD using BBR as the TCP stack and see if the results are any better for dropbox.
FWIW, my corp openvpn is kinda terrible. My upload speeds via the vpn did not improve at all when I moved and upgraded from 10Mb/s to 1Gb/s upstream speeds. When I switched to BBR, my bandwidth went from ~8Mb/s -> 60Mbs, which I think is the limit of the corp vpn endpoint.
It would be interesting to re-try the experiment on Linux or FreeBSD using BBR as the TCP stack and see if the results are any better for dropbox.
FWIW, my corp openvpn is kinda terrible. My upload speeds via the vpn did not improve at all when I moved and upgraded from 10Mb/s to 1Gb/s upstream speeds. When I switched to BBR, my bandwidth went from ~8Mb/s -> 60Mbs, which I think is the limit of the corp vpn endpoint.