Look how long games live currently. This is not 90’s or early 2000 anymore. Game development and marketing costs are muvh much bigger than used to be. It is no longer profitable to sent new game every 2-3 years.
If publishers could release a title and subsequent sequels every 2-3 years they'd be jumping for joy. The biggest cost in game development is staff - the more product they can get to market - the more income generated. Iterative titles like Gran Turismo (and all sports titles) have different development cycles to traditional single-player games which are rebuilt from the ground-up, with new game worlds, all-new story etc.
They already put microtransactions to monetise it + the game still sales very well
Sales legs for GT7 are very strong but we have only just passed it's 2 year launch anniversary. By year 3, and especially year 4, there'll be a significant drop-off and the market will be ready for a sequel. Microtransactions are one means to generate post-launch income - but it's rather outdated and unattractive to most players. I haven't spent a penny on such things but I would be a regular purchaser of cosmetic items (wheels, aero parts, interior items), plus more substantial DLC like car and track packs.
Ps5 pro is here in late 2024 probably. You would burn money for updating GT7 just to send new game just an year later? That doesn’t make sense. Remember GT8 is not just development cost but huge marketing cost…
I'd expect every major AAA title from Sony to receive a PS5 Pro update - for most it would be a case of utilising existing tech. IE, RT support in gameplay, not just replays. Higher LOD car models, higher resolution textures, effects and so on. If, as I suspect, GT7 is one of the showcase titles for PS5 Pro, it make sense to invest.
There is really not that big difference beetween PS4 and PS5 you are really overhyping „next gen only” games. Look at Forza it is next gen only and it fails in nearly all aspects…
New game engines are made to be scalable. PD really didn’t cut anything just to make GT7 run on PS4.
There are diminishing returns but a next-gen only Gran Turismo that maximises PS5 will not be able to run on PS4. Even with reduced resolution and (if you're willing to compromise) sub 60FPS. I'm sure PD's game engine has already undergone updates to take advantage of new tech like the SSD.
For whatever reason (CPU I presume) GT Sophy cannot run on PS4. Larger grids and more complex physics will be possible on PS5, but there has to be parity with PS4 for cross-gen online play. Likewise, streaming much higher quality track assets (see Nanite on Unreal Engine 5) will be possible on PS5 thanks to the SSD. But PD had to limit how much they leant into this as they needed a version of GT7 up and running on the PS4's archaic HDD.
RT is another area that will fundamentally change how PD builds their lighting engine. This is a non-starter on PS4 so they stuck with tried and tested methods for GT7. Plus the added bonus of RT shadows in replays on PS5. For a PS5 only SKU (and particularly PS5 Pro) they can put the R&D into more extensive use of RT.
Obvious reasons being GT7 was being developed since 2018 on the base PS4 and the fact that the PS5 had barely sold 20 million units compared to the PS4 with 115 million units? Sony prioritises money, GT7 wasn't even a launch title and was still a crossplatform game, the same will happen with GT8. They'll just restrict some features on the PS6 version like GT7 with Sophy and PSVR2.
Sales data indicates it was a mistake to continue with cross-gen beyond PS5's launch window. Particularly a title like GT7 with it's long sales legs. I expect GT8 will be PS5 only as I don't see a scenario where we don't get an all new Gran Turismo for 6 years. As for GT9, sure, that could be cross-gen PS5/PS6 if it arrives '28-'30!. But I don't see that being a major issue as the switch to SSD and RT was already made this gen.