> start my own US based company that "sold" open-source software so that it'd have a US-flagged company
That is the business model for Redhat, Ubuntu, SUSE, and other GNU/Linux companies. You can download it for free or pay a subscription to have emails and phonecalls answered.
You can download Red Hat for free, but you won't be able to use it without registering. Rocky Linux has done a good job of making a free Red Hat though. Been using it for my RHCSA recently
The difference is really I wouldn't be developing any of the software. I'm literally selling things you can get off of say GitHub.
Although I'd probably need to not be completely blunt about it. It'd just be mostly an open secret where any of the dev teams would know that's exactly what I'm doing (and any sort of LICENSE file would make it dead obvious) but to procurement and whatnot it just looks like you're funneling money to me in exchange for some software.
That is the business model for Redhat, Ubuntu, SUSE, and other GNU/Linux companies. You can download it for free or pay a subscription to have emails and phonecalls answered.