Yet when AMD and Nvidia launched their latest graphics cards, they started with the 7900XTX and RTX 4090 respectively, then worked their way down (with the lowest end models still to come).For the last 12+ years CPU silicon has been developed from the lower end to the higher and rolled out in a specific manner due to yields, as the nm size has gone down dramatically complexity has a much lower success rate so it takes a while especially when using a newly developed process on wafers. You will get failures in certain parts of the SoC, which is how we get cut down GPU variants, etc. Building the same architecture out of multiple cores or chiplets that are the same allows them to not totally waste a whole wafer on some unique complex thing, they can buiild a bunch of Max CPUs, some will have less working GPU cores, etc. and the best ones will be fully functional & linked via the communication fabric, which itself is also very complex.
Apple cannot simply just "choose to release what they want" in any sizable quantity. Since it's a Mac Pro which sells in low numbers it's theoretically possible, but Tim Cook isn't going to waste the absolutely insane amount of money on that. You'd have like $20,000 CPUs if you launched some Quad ultra first.
So many people have no damn idea what they're talking about in this thread, I don't understand how everyone has gotten so confidently incorrect over the last decade without doing any research at all into the technical aspects of how these things are made. I know this sounds like I'm being a jerk, but doing the work to learn about things will help you in life in general – don't just wing it and pretend you know what's going on, research and learn about something you don't quite know without just spouting off nonsense.
When Intel released their 13th gen in October last year, they released their entire desktop line up at once, with the high-end i9-13900K naturally getting the lion's share of press attention.
The Ultra is just a pair of mainstream laptop CPUs. The only reason for low yields with Ultras would be manufacturing issues with the UltraFusion link.