Speed problem on Route10

I’d suggest a speed check from the Route10 to narrow it down further. Also, perform a speed check from a WiFi device (with a connection that would saturate the nominal ISP speed).

Maybe you have already seen the post by @dalewhlrr, and if not check here for setting up and running speedtest on Route10 through SSH+CLI:

Also, as a further test, set up Route10 as an iperf3 server and check from the PC as client, just to make sure there isn’t something coincidentally fishy with cables or the PC network card.