2021W25
Cs is a very populair game, thousends of people play at all hours of the day.
All those players are divided though, there is not one big pool where they all play in.
(I haven't checked these numbers) 90% of the people playing csgo do so via the normal match making system thats in the game itself. I recon about half of those players play the "casual" gamemodes for fun. The other half play the compatative mode only. This mode is equal to what the professionals play in their tournaments (albeit with a few server options tweaked). 5v5, playing on a subsection of the maps know as the "active duty" maps. I'm only interested in that gamemode.
The MM (match making) players have a semi hidden score, which is categorised into ranks. At the bottom with silver1 through 5, then gold stars, evenutally reaching the "Global Elite" ranking. Only 0.1% of all MM players currently have that rank.
As the game has grown and matured, the average skill level of all players has also slowly risen. There is still a pretty big skill discrepency in the Global Elite rank itself! Here's where the other 10% of csgo players reside, They're not playing the MM built into the game, they've reached out for 3rd parties to organise games via their platform.
A couple of the most populair are Faceit, Esea, and Esportal. There are many more regional ones hosting a fairly sizable chunk of the competative playerbase.
These 3d party sites have their own ranking system, and are generally populated with even more 'hardcore' csgo players. Most of these 3rd parties also host small tournaments for players willing (and able) to compete and fight their way to the top.
Faceit is a very populair example in europe and the CIS region. Their ranking system goes from level 1 to 10. They've made a exclusive leage called "Faceit Pro Leage" where players, after proving their skill in the various regional circuits, get to compete with and against professional players. Some of whom have come through the very same yourney.