Problem #1: they are closed source. Good luck verifying their security.
Problem #2: it is in the best interest of nation states to be able to break the VPNs and it's in the best interest of large vendors to quietly cooperate with the government.
Problem #2: it is in the best interest of nation states to be able to break the VPNs and it's in the best interest of large vendors to quietly cooperate with the government.
Corporate espionage backed by nation state actors is a real thing, and there is nothing wrong with wanting to secure yourself against it while running a normal business.