Fix and Insight Requested: Unreliable internet connectivity for weeks (detailed metrics and equipment)

We upgraded our Xfinity tv/internet plan about one month ago and have been experiencing almost hourly erratic internet connection (all sites and services will render slowly or not at all for a few minutes) since, both on wireless devices and devices connected directly to the XB7-T by ethernet (we don’t use a separate router). I’ve done many rounds of power cycling and even a hard factory reset for the XB7-T. Still, the wired and wireless connectivity issues remain. To note, our internet service is the one gigabit down plan. Our tv boxes are the XG1v4-a and the Xi6. I will post the XB7-T signal metrics at the bottom. 

I will say that while our household isn't using a MoCA system, the XB7-T seems permanently stuck in MoCA mode, as others have posted about for years. Even the hard reset only gave us one hour before the gateway's MoCA mode automatically came back on. I remain uncertain if this is just how all XB7-Ts operate, or if MoCA mode is automatic and required while using tv boxes like mine (which I vaguely understand they communicate to each other through their own MoCA). The underground outside cable line terminates into what appears to be a generic-looking 3db attenuator, which then leads cable into a three-way split Commscope 5-1002 MHz Splitter (SV-3G), which brings three cable lines inside the house. Seemingly there is no MoCA POE filter in this chain? Also, from what I can tell, there are no splitters, amplifiers, attenuators, MoCA filters, or other connectivity accessories after this outside 3-way splitter. Hopefully this is useful diagnostic information. 

The XB7-T signal metrics are below. Thanks for anyone’s help and insight!