Very true, although I assume that most or all of those listed have their own form of ITAR. Space (mostly defense) is inherently siloed to country borders.
I can't speak for the other nations, but Space technology in Canada is controlled under the Controlled Goods Program (CGP). A CGP clearance is obtainable as a Permanent Resident. No citizenship required. Various Canadian companies are suppliers/partners for space projects in the US. For example the Artemis project is using the Canadian company MDA as a key supplier (to manufacture space robotic systems, including a newer version of the robotic arm currently on the ISS). SpaceX also has a number of Canadian suppliers, although their involvement is not advertised very much.
> Isn't that most large capital intensive efforts?
No.
For example in university i was part of a satellite design competition. We couldn’t let Chinese nationals on the team or we’d be breaking the law. There was a list of approved countries a team member could have citizenship from, if not we’d be guilty of violating export controls.