You may have local issues. I ran a series of iperf3 tests in a small but non-trivial network and was surprised. There was a 100Mbps switch that had been forgott

You may have local issues. I ran a series of iperf3 tests in a small but non-trivial network and was surprised. There was a 100Mbps switch that had been forgotten about. Also a wifi network running off a Power over Ethernet link which was 3Mbps compared with 50Mbps over fairly poor Wifi it was supposed to be superior to, which looks pretty darn good to the POE link. A cheap switch and two LAN cables later things are so much better.