Skylake-X certainly would have existed regardless of Ryzen, Intel wants to sell these chips to Google/Amazon/Facebook as Xeons. The idea that this uarch is a reaction to AMD is absurd, this uarch has been on the roadmap for years and at most was pulled forward a few months.

People will attribute anything one of AMD's competitors does to fear of AMD - 780 Ti, 980 Ti, 1080 Ti, Skylake-X, you name it. It's frankly a little comical given the actual amount of competition AMD put up with Bulldozer and Fiji/Polaris/Vega against Haswell/Skylake and Maxwell/Pascal - which is to say, hardly any. NVIDIA and Intel both have their own yield strategies and release schedules that are largely independent of what AMD does. Intel and NVIDIA are tweaking prices and specific launch dates - that's about the extent of AMD's impact on their competitors so far.

(although Intel is definitely paying attention to Threadripper/Epyc now, and will be pushing core count up on consumer chipsets starting with Coffee Lake and presumably Cannonlake as well)

The real problems with Skylake-X are chipset cost, power consumption, shitty partner boards with insulators on the VRMs, and TIM. None of those have anything to do with a "rushed launch", all of those are issues that have been slow-boiling for years now.