The only two quad-core Kaby Lake-X CPUs launched back in summer 2017were supposed to provide an entry point for the Intel's HEDT chips, but sold very poorly, because the Coffee Lake hexa-cores launched just a few months later. OEMs and resellers will be able to order the two chips up until November 30 and Intel will be pulling the plug on May 31, 2019.
https://www.notebookcheck.net/Intel-discontinues-its-Kaby-Lake-X-series-after-10-months-from-launch.301744.0.html
well they were pretty pointless, didn't even have more PCIe like one would expect from a HEDT product