I've shared multiple technical explanations in this thread (as well as a highly reputable source on netcode:
viewtopic.php?f=10&t=7771&start=30#p60074), and you've discounted them all in haste and with very little reason.
Your expectations are off-the-charts, and it's evident by now that much of that is due to a lack of experience and familiarity with fundamental technical subjects that provide an understanding on the inherit failings and limitations of current-gen technology.
For those of us who are more acquainted with how all this works, all of these obnoxious (oft unavoidable) technological and infrastructural limitations are simply par for the course, and short of partial mitigation on the user-side, we're at the mercy of their originators, and any breakthroughs said originators make, iterate on, and implement over time.
Your latest and previous videos don't "show" anything abnormal, and everything you've shared thus far has pointed to entirely known per-game performance, netcode, and ISP issues, all of which can create problems that come and go.
As for you having tried cellular connections, those are even worse for online games, and if all the ISPs you've tried are running on cable, then those companies are all using the same infrastructure of your neighborhood, as is the neighbor's connection you tried, which doesn't rule out internet issues in your particular case at all.
Regarding EMI, you yourself have admitted you've tried the suggested solutions that have worked for others that claim they experience said issue, and none have solved yours.
If you refuse to accept the possibility that what you're seeing is within normal variance of imperfect game performance offline/online, and imperfect netcode/ISP performance online, and you truly think you're right about it being an interference or electrical issue in your particular house, and/or an infrastructure issues plaguing your entire area, your only
viable option is
to move.
):