For gaming. 8C/16T is the sweet spot, as you can see in the results. Exact same perf as 10C/20T and 8C/16T will usually allow for slightly higher clockspeeds which is preferable.
I'd rather have 6C/12T over 8C/8T considering next gen consoles gets SMT, meaning New AAA Games will take use (like Battlefield series have done for years). Console hardware predicts PC gaming requirements, so Expect RAM and VRAM requirement bump soon + more CPU cores needed. The days of Quad Core Gaming will be gone soon. Even SMT is not going to save Quads this time.
8C/16T will be enough for the entirety of next gen consoles, meaning 6-8 years into the future.
I would like to see focus on clockspeeds now. Answer is NOT more cores and threads for consumers/gamers, we need IPC and/or clockspeed improvement.
This is what Rocket Late and Zen 3 is supposed to bring, but I don't expect something really good before 2022+ (new arch and platforms from both Intel and AMD with DDR5 and PCIe 5.0 support).
Zen 3 and Rocket Lake will just be "more of the same" (performance-wise) and both Intel 400 series platform and AM4 is a dead end now. You won't see any leaps this time.