Occams Razor still true (simplest explanation). There is nothing more frustrating than paying top $$ for a fast internet connection (spectrum with wifi 6 router) and getting actual MBS downloads at 1/5 to 1/10th the speeds when using a vpn (IPVan or SurfS). Mesh satellites and ethernet wires may help some but there is nothing like reducing the distance from the router to the tv or android box. In my TV room, there was a covered receptacle that was an unused node from the cable entry at the other end of the house. It was found using a Klein Tools VDV500-820 Wire Tracer (get on Amazon). I then set up my cable modem-router 8 feet from the Tv and box(fire cube gen 3). This is obviously not available for all—but don’t fail to give it a try. I pay for 500mbs download from Spectrum; now without vpn 460mbs; with IPVan or SurfS 360-400 mbs.
I’m on the 5th floor of a 7 storey highrise and that’s what my ISP did. Found a cable box with a 1 inch conduit and ran a Fiber cable all the way from the main floor, installed an ORT and ran a 6 foot cat 5e to my modem/router that sits right beside my TV and 5 ft from my Shield Pro. Overkill speeds but I get all of what I pay for.
It’s definitely in the list of troubleshooting steps for optimizing internet speed through a VPN. It, however, is just a piece of the complete puzzle. Mesh routers would help in difficult, multi-story houses, and put the router nodes in point-of-use rooms, so that could be an option too. Then after that is optimized, dialing in the VPN settings, box settings, etc etc hopefully get you where you are getting the most “bang-for-your buck” out of your internet speed.