Tempest mission profile (previously) rules out a carrier based version.
I don’t think that’s what the article is suggesting, rather that, if both NGAD and F/A-XX get scrubbed, buying into Tempest would provide opportunities for the US engine manufacturers to press on with NGAP and other 6th Gen items such as CCA.
The problem being those are exactly the technologies the UK, Japan and Italy want to develop independently as national key technologies - not buy into US ITAR programmes.