Given the Japanese decision to go with the UK and Italy in this new project (instead of the US), in a major change of direction for Japan re: their long term defence and industrial development policies, it appears that even the closest US allies aren’t really being let near the next generation US fighter and its technology (F-22 replacement but likely rather more than that).
If Japan had an equivalent deal from the US on the table they wouldn’t have gone with the UK and Italy option. The US offer must have been significantly inferior from a Japanese perspective. In that context I would doubt that even the likes of the UK, Canada and Australia will have any access/ offers anytime soon. Appears it’s F-35s or bust for the moment re: 5 generation or greater product offerings from the US to its allies.
There is a wider point about if this apparent US position (apparently forcing Japan to find new partners) is part of wider ongoing US policy evolution under administrations of both US parties. Some will fear an overly protectionist position re: technology sharing even with very close allies, others may fear an even darker paranoid and xenophobic-tinged “America First” evolution of positions driving decisions.
The apparent difference between the position taken re: Japan and its future fighter and taken re: Australia re: AUKUS and nuclear subs is, at least for the moment, very noticeable but hopefully will prove to be more apparent than real (e.g. Japanese and other allies access to AUKUS equivalent status and partnership with the US).