90-95% of the FPS in games is from the GPU,
intel having 5-10% more FPS I barely noticeable at best... I mean sure it's up to 10% but if you're doing literally anything else than gaming on your computer AMD crushes Intel in pretty much every professional use.
It depends on what you are comparing. If you're comparing a budget CPU vs. the top mainstream CPU with a fixed GPU in a budget gaming build, then yes, paying e.g. $100 extra for 5% performance is a waste, money which could have been put into a better GPU.
But when you're comparing similarly priced CPUs and one gives more performance, you go for the best performing one.
Also Memory speed has little to no effect on Intel CPU, you can be having 2600Mhz or 4266Mhz you gain what ... 5%
Well, gains beyond 2666 MHz DDR4 in gaming are more like 1-2%, well within the margin of error, except for a few edge cases. It's simply pointless.
But more importantly, running memory at higher speeds depends on both motherboard support and the die quality of the CPU. Even if you buy a kit with a high rated speed and a motherboard which supports it, there is no guarantee you will be able to run in. And even if you do so, it will probably not be stable for years of load. High speed memory is probably the primary thing gamers waste money on.
Now Ryzen 7nm is on the horizon, probably going to support ddr5 at some point, which will Obviously boost even more its perf if Intel doesn't changes its Arch
Ryzen on 7nm (Zen 2) is still far away, and it will primarily compete with Intel's Ice Lake.
Wait until the next major architecture (what is it, Cascade Lake now?), which should be on 10nm, to see what they can really do...
HEDT: Skylake-X/SP -> Cascade Lake-X/SP(14nm 2018) -> Cooper Lake-X/SP (14nm 2019) -> Ice Lake-X/SP(10nm 2020)
Mainstream: Coffee Lake/Cannon Lake/Whiskey Lake -> Ice Lake (10nm 2019) -> Tiger Lake (?) -> Sapphire Rapids (?)