It all boils down to politics, not what the services require nor the capabilities of weapons systems.
Comac is Chinese, and it was mentioned. Maybe try actually reading the article before posting a comment.
Read the linked article and you'll understand why.
Spending billions on new designs is unnecessary. The missions are known. The ranges are known. The cargo is known. Mothball the tooling and in a decade's time restart and build a 'B' variant, as...
Delays on actually making a decision. The multiple and costly F35 delays have been in construction and testing.