Perhaps someone will be able to make a speedtest towards an iPerf server (or even has Gbit Internet).
High speed data mode:
iperf3 -c 10.10.10.10
'Connecting to host 10.10.10.10, port 5201
[ 4] local 10.10.10.186 port 54276 connected to 10.10.10.10 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 115 MBytes 967 Mbits/sec
[ 4] 1.00-2.00 sec 112 MBytes 941 Mbits/sec
[ 4] 2.00-3.00 sec 112 MBytes 941 Mbits/sec
[ 4] 3.00-4.00 sec 112 MBytes 941 Mbits/sec
[ 4] 4.00-5.00 sec 112 MBytes 942 Mbits/sec
[ 4] 5.00-6.00 sec 112 MBytes 941 Mbits/sec
[ 4] 6.00-7.00 sec 112 MBytes 941 Mbits/sec
[ 4] 7.00-8.00 sec 112 MBytes 941 Mbits/sec
[ 4] 8.00-9.00 sec 112 MBytes 941 Mbits/sec
[ 4] 9.00-10.00 sec 112 MBytes 941 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 1.10 GBytes 944 Mbits/sec sender
[ 4] 0.00-10.00 sec 1.10 GBytes 941 Mbits/sec receiver
High resolution mode:
iperf3 -c 10.10.10.10
Connecting to host 10.10.10.10, port 5201
[ 4] local 10.10.10.186 port 54425 connected to 10.10.10.10 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 44.0 MBytes 369 Mbits/sec
[ 4] 1.00-2.00 sec 40.5 MBytes 339 Mbits/sec
[ 4] 2.00-3.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 3.00-4.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 4.00-5.00 sec 40.5 MBytes 339 Mbits/sec
[ 4] 5.00-6.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 6.00-7.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 7.00-8.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 8.00-9.00 sec 40.4 MBytes 339 Mbits/sec
[ 4] 9.00-10.00 sec 40.4 MBytes 339 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 408 MBytes 342 Mbits/sec sender
[ 4] 0.00-10.00 sec 404 MBytes 339 Mbits/sec receiver
Same results with <usb-c only cable for video and usb hub> and <usb-c to display port and usb-c hub cable>