This is almost certainly much less interesting than it sounds. It's effectively saying that if you're in the US, your network path is probably from one part of the US to another for many of your communications. (eg: Utah to Palo Alto, New York to Virginia, etc) These communications would not be surveilled.
But, if you send 100% of your communications through a consumer VPN and therefore much of your network traffic originates outside the US, your traffic might end up getting automatically collected.
THEORETICALLY the government has _some_ restrictions against monitoring US citizens (https://www.brennancenter.org/our-work/research-reports/soci...), and it sounds like none of those are deemed to apply if you're using a VPN, per the original article.
Many VPNs are owned and operated by organized crime, intelligence services from all kinds of nations, and cops. The idea that a VPN somehow protects you does not enjoy a rational basis.
There is a logical counterpoint, which is that if a foreign user uses a US VPN, it immunizes them from surveillance to the extend their connection to the VPN stays secure.
There is no choice but to use a foreign VPN to access certain sites, specifically certain crypto and prediction market sites that otherwise remain inaccessible.
But, if you send 100% of your communications through a consumer VPN and therefore much of your network traffic originates outside the US, your traffic might end up getting automatically collected.