For a gaming only computer, I wouldn't mind building a system with the 7700k if intel dropped the price to $200ish. It's a fast 4 core chip and if gaming were of only concern, that would be the ideal one.
What I really like about the Ryzen 1800x is that it does ok with single thread performance,, the multi-8 core just screams...
I do a lot of system development that requires compiling Android O/S and linux kernels, and some of those running on my existing 4 core old processor takes like 4-6 hours from a clean build state. Video processing pipelines take 1/2 hour for 15 minute clips... Cutting that down to 1/4-1/5 of the time it takes with a Ryzen 1800x $499 processor instead of a comparable $1000+ processor from intel would be ideal. And for occasional gaming with older less optimized games that are more dependent on single threaded performance, the 1800x is alright.