GCAP seems to have a lot more momentum behind it than FCAS, I doubt that it's going to fizzle out. Japan's involvement is novel to be sure, but the UK and Italy have a long history of collaboration, not only with previous European combat aircraft projects such as Typhoon and Tornado, but also helicopters (AgustaWestland), the common heritage of Type 45/Horizon and EMPAR/SAMPSON, etc. Given the multinational nature of the project and its significance for each of the national partners, I think a dedicated thread could be justified rather than having piecemeal updates scattered across various threads.
I would also be very surprised if GCAP fizzles out, seems like some budgetary snags at the moment which are pretty common for projects this expensive. With the erratic nature of the U.S. and apparent weakening of Europe-US military alliances, I would be shocked if it ended up falling through, it's an extremely important project for Italian, Japanese, and British aerospace companies.
A program named GCAP or Tempest or whatever may live for ever so long as politician's keep the name, but the essential outcome may fizzle out or becomes a moving target. For example, when Tempest was concieved ten years ago it was to replace Eurofighter and perceived as a F-22/F-35/J-20 equivlant same as Japan's F-X. Now J-36 is flying, is GCAP going to move up one generation or stay as J-20? If it is the later it would become obsolete at introduction. If it is aiming at J-36, GCAP becomes a moving target, meaning the original 5th gen GCAP is dead already.
