the reason why the U.S. cannot win a case in the WTO for forced technology transfer

In any case, no one can claim that foreign companies were forced to operate in the Chinese market. The argument that US firms have been forced to transfer their technology to China thus lacks significance.

In fact, that argument was never backed by persuasive evidence. While the US trade representative, which compiled the Section 301 report, claims to have conducted many surveys, all respondents are anonymous and their assertions are little more than hearsay – nothing that would be admissible in a court of law.