The US government blocks all kinds of company sales. Sometimes for anti monopoly reasons, sometimes for national security reasons.

10 years ago I worked for a company with less than 2,000 people. We made a chip that was used by a few gigantic companies over 150K employees. There were only 3 companies that made this kind of product. My company tried to sell a business unit with about 200 people to our competitor and get out of this market. Our two gigantic customers went to the US FTC Federal Trade Commission and got them to block the deal over anti competitive concerns. With only 2 competitors these gigantic companies expected that they would have to pay more per chip. They used their influence to get the government to block the deal.

At least some of the equipment (EUV machines being the big example but even things like high bandwidth oscilloscopes and many other tools we never hear about) are already export restricted (export is still possible but requires approval).

Whether the executive could place a blanket "no export" on all of it without a legal battle is a very different question.

Edit: this is only for whether or not the equipment can leave US soil. Whether it can be sold to a foreign company but stay in the US is a different question (the answer is yes if I had to guess)

There’s only a handful of leading edge customers. If you can’t peal off TSMC customers you’re toast.