Willing to bet this is because of Xe development.

SweenJM:

Sourcing chips from your competition seems like a dead-end anyways (not taking anything away from the quality of the product itself). I would tend to agree with you. The intel igpu was due for an overhaul some time ago (Iris was better, but still kinda meh), but they certainly might as well take full advantage of their new graphics chips and designs. These kaby lake-g chips seemed like more of a "proof of concept" design then an actual long term solution from the start........they are super cool though. Would not be surprised to see a very similar chip package with a Xe chips instead of Vega.

What doesn't help is I'm pretty sure these chips were only used by Intel for their NUC. If Apple used them, it would have been different seeing Apple is pretty Pro Intel cpu and AMD gpu.

Was tempted to pickup a 7700K as an upgrade to my 6600K, but the prices are still crazy for a 4 core chip, this will likely push them higher. New motherboard it is then!

Few days ago I had to run live diagnostics and tune my old 1999 Camaro LS1 with HP Tuners software. I never had a problem with the quad core Atom processor. I forgot what model but It's one of the last Atom's that INTEL made for Laptops. Mind you I don't use the internet with it.................................. Well Windows 10 Defender was updating and everything was fine. So I do a full scan and notice my laptop was running slow and freezing up and finally I had to restart it the hard way. Well again it was pegged at 100% right when I logged in again. The CPU got super hot which never does. How did I fix it? I had to use AIRPLANE mode quickly before it ran slow and or permanently freeze up. Bam from 100% usage it went back to it's normal low percentage. What's my point? Everyday I hate INTEL more and more. INTEL deserves this karma with AMD breathing on their neck.

Richard Nutman:

Was tempted to pickup a 7700K as an upgrade to my 6600K, but the prices are still crazy for a 4 core chip, this will likely push them higher. New motherboard it is then!

If you only buy new then the prices do seem high, i picked mine up in Feb 2018 for £215, the seller wanted £250 but i offered him £215 and had no problem accepting, i then spent another £15 to get it delidded, i too upgraded directly from an i5 6600k and am very happy, for gaming the i7 7700k will be your best bet as the boost from the 8700k, 9700k or even the 9900k in most of todays games is minimal