People are bending over backwards to come to try to find some deep reason, but I think the reason is simple - the people in charge are not particularly farsighted nor insightful. It's simply short-term thinking without consideration of long-term consequences - it's not limited to just businesses.

For another example, the reason Chinese are not allowed on the 'international' ISS is because of the Wolf Amendment. [1] The idea was that if we just allowed them onto the ISS they'd steal all of our elite tech or something. Within a decade they had launched their own space station and carried out various revolutionary space activities.

And of course all of that happened while the ISS itself continues to deteriorate with no replacement in sight. And when China did an unprecedented sample return mission from the far side of the Moon and offered the whole world access to samples, US researchers had to jump through a bunch of hoops to receive them, again thanks to the same law.

It's just myopia.

[1] - https://en.wikipedia.org/wiki/Wolf_Amendment