Have been regularly having ping spikes and very slow upload speeds

I currently subscribe to the 200 mbps/5 mbps tier xfinity internet.

I usually get 240 down (great!) and about 1-2 mbps up (oof) which makes video conferencing  quite difficult.

The main issue though is the latency of the connection. We randomly get ping spikes to 8.8.8.8 (google) all the way up to 6000 ms on an ethernet connection while the latency from my computer to modem is 1-3 ms.

We have had 2 techs over to check ingress, replace cable connectors, remove splitters and remove a noise filter and they insisted the connection was fine. I even tried different models of comcast modems to see if they would address the issue including the XB3 and XB6. I currently use the TP-Link TC 7650 which generally performs well until the network starts getting crowded.

I generally use ethernet for my testing but I've tested using two different routers: Google Wifi and TP-Link Archer C5v2

Can anyone help me resolve this issue?

My Modem signal strengths are here:
https://imgur.com/a/RsinsIm