For gaming, the high end Intel and AMD CPUs are trading blows. They are pretty much on par and the differences in gaming performance are very small but if you do any multicore workloads then AMD mobs the floor with Intel.
There’s also not much room for overclocking anymore. Intel is still easier to overclock but you won’t be able to do stuff like oc’ing a 2.67GHz i7 920 to 4GHz and more than doubling gaming performance in the process (I loved this cpu).
Additionally, from what I have seen online OC’ing a modern Intel CPU makes them extremely power hungry.
In AMDs case it’s not even worth doing an all core overclock as you will lose the single core boost which is very beneficial in a lot of gaming titles and most of their CPUs will boost quite a bit higher than their advertised maximum (for example my 5900X clocks to 4.95GHz single core on stock settings).
What you can do on AMD is to tweak Vcore and PBO to increase the boost frequency. There are tools that make that pretty easy like the Ryzen clocktuner. High speed RAM with low latency is also extremely beneficial to Zen 3 CPUs
I went from an i7 6700k running at 4.5GHz to the R9 5900X and noticed a roughly 20-25fps increase in DCS and more than tripled my frame rate in MSFS 2020 (that was the really crazy part). Needless to say, I am very happy with the 5900X.
Edit: 1TB or 2TB M.2 NVMe drive with 64GB RAM or more if you are building a high end flightsim rig. DCS will thank you with faster loading times and completely eliminate the occasional stutter. Preload radius to maximum and be done with it.
Quick CPUz benchmark I did a while back