I am hard-pressed to say that it looks like a suitable benchmark. It's hard to find a desktop CPU released in the past five years that can't provide good performance for a game like that.
People still benchmark CS:GO because it is one of the few games that is CPU bound that still actively being played today. It's one of the few games where a single core performance and memory latency has a big impact on overall performance.
Intel always had a huge lead on CS:GO until Zen 2 where the gap finally closes up, which is why a lot of people is referring to CS:GO benchmark when talking about Zen 2 in context of gaming.
actually a lot of pro players are streamers, so they at least need a good cpu for game+stream. some even have a setup with two computers.
actually streaming games (especially new ones) still needs at least the i7's.
Some CS Go players believe (and maybe is true) that having high FPSes live around 300 give them an advantage so they will try to make the FPS number as large as possible. Such a gamer will probably pay a ton more money to get from 2500 FPS to 300 FPS. They would also have monitor and mouse+ keyboards with low latency.
So from my reading this "elite/full time" gamers will still buy an expensive CPU if they get 10 extra frames (but forget that in real life your PC has more programs running in background so reality may not match the benchmarks)
For people wondering why, it has mainly to with the fact that mouse polling rates are tied to FPS meaning that you still have heavy incentive to go above the FPS your monitor could handle.
This video (https://www.youtube.com/watch?v=hjWSRTYV8e0) does a really good job explaining frame latency in CSGO and why you can benefit from running at FPS significantly higher than your refresh rate, and why vertical sync doesn't solve it like it should. The game is free now, so I'd highly recommend trying it out if you're doubtful about a smoothness difference between 100 and 250-300 FPS.
The real reason is, I only really play csgo and pubg, I have X$ to spend on a CPU. Previously if you looked at them market, tier-to-tier amd vs intel - intel always was the stronger performer at the CSGO. Why spend X$ and get 250fps when you can spend the same and get 300fps?
I'm not sure whether they update the minimum system requirements alongside the game. Keep in mind, CSGO is from 2012 and has received numerous updates, and looks, feels and sounds completely different today.
When I first bought my main laptop in 2017, I could play somewhat smoothly at 1080p, now I have to use 720p.
It's an interesting side-effect, before Steam and other content-platforms, games titles iterated much faster.
EDIT: Then again, when I think about CoD, I'll retract my last sentence.
That’s not the only game LTT uses to benchmark with, but they include it because of its popularity and I suspect because it normally runs at such insane frame rates that differences show up more readily—much easier to tell 220 FPS vs 240 FPS than 59.5 vs 60.
https://store.steampowered.com/app/730/CounterStrike_Global_...
I am hard-pressed to say that it looks like a suitable benchmark. It's hard to find a desktop CPU released in the past five years that can't provide good performance for a game like that.