Apple's mobile devices are where their real revenue lies, and as a result their laptops and desktops and their Operating Systems for such have been B-team efforts. This seems like an effort to effectively sunset all their Desktop and Laptop efforts and the "general" OS X Operating System, and have everything running some version of iOS, rather than have separated iOS and OS X.
It doesn't make much sense for Apple to effectively point fingers at Intel when Apple hasn't even been properly using Intel's processors anyway. Even their highest-end offerings have insufficient cooling to prevent the CPU from thermal throttling.
The Core i9 Processor is not "new"- as your second quote mentions it was announced last year and they have been available since around November 2017. They aren't relevant to Apple, however, who as mentioned is barely able to engineer their systems for TDP of the i7 processors in their highest end SKUs.
They are fundamentally the "Extreme Edition" processors which provide the highest core count, overclocking, and performance at a massive price premium.. They aren't even an upgrade option from i3/i5/i7 since they actually use a different socket.