I think the current rumor is that only one of the chiplets will have the extra cache though, so you'll have 8 cores with the big cache and 8 cores with the normal cache.
If they make one with extra cache on both CCDs, it would probably get some kind of AI branding and be at a significantly higher price point. Current games would hardly benefit from 16 cores all with that much cache.
The main benefit is that it's a no-compromise product. High single thread performance for games and there's more of those cores for productivity, it'd be the best workstation CPU and the best gaming CPU in one package.
They've solved a lot of the manufacturing issues since then and since it's already a premium product, why not go all in? There might be cases where the extra cache helps performance in heavily multithreaded workloads, also niche usecases like running the chip in a headless gaming server, which would allow for splitting of the CPU into two for simultaneous game streaming without significantly compromising performance for either client.
That's the point of no compromise, sometimes it's nice to have 100% benefit (not to say that making a single CCD cache version doesn't make sense as a product).
