I have a h2d model router connected to the cable modem.
The speed tested directly from the modem is 500 mbps. This is also the speed reported by the router in the google home up.
The speed out from the modem using both the wifi and the wired connection is around 80 to 90 mbps.
I powered it off and I restarted the network and no luck. The mesh test came out ok.
Any time I see a wired speed test coming in under 100Mbps I immediately suspect the Ethernet cable (or cables), any Ethernet switches, or any of the Ethernet ports involved. To diagnose this, I would focus on that first. I would connect an Ethernet device (something you know for sure has a 1Gbps Ethernet port) directly to the Nest WiFi Router's LAN Ethernet port using a Cat 5e Ethernet cable (Cat 6 cables are not necessary and since they are more stiff than Cat 5e, they can actually cause poor connections to any port where they'd need to bend close to the port). I would then look at the connection details for the Ethernet port on that device (e.g., a laptop or desktop computer) to make sure it's negotiating a 1Gbps Ethernet connection rather than falling back to 100Mbps. Hopefully, this process will produce some clues that may be useful in resolving the issue.
You said earlier that the internet speed test built in to the Nest WiFi Router was showing the expected speeds, which rules out the Ethernet between the router and the modem being the issue. However, if that speed test isn't consistently as expected, then you may need to focus first on that link (modem to Nest WiFi Router WAN Ethernet port). The WiFi speed being slower may be another issue, but it could also be a hint the issue is between the router and the modem.
Thanks for the help, MichaelP.
tom6663, I hope you've got the answer you're looking for.
I'm sorry you feel that way, xxhallowsxx. Have you had the chance to try the steps above?
Give these steps a whirl:
Let us know how it goes.