1. Overwatch, the competitive ladder, is not a casual game. Everything you mentioned for CS, happens in Overwatch too; it's a esport that had millions invested.
2. The top 5% of CSGO ranked is Legendary Eagle. There is a world of difference between Legendary Eagle and Global Elite (top .75%). And even between those 2 ranks, there are two other ranks. The top 5% isn't that good; and Global Elite itself is still a step below actual pros.
It's like being a tech worker who earns $400k a year and saying "I don't earn that much, there's people who do what I do clearing seven figures a year, and others who were able to retire in their early 30s and don't even have to work anymore because they became so wealthy from work." Sure, it's not a lot of money compared to those people, but it is when compared to the vast majority of wage earners in any region in the world.
EDIT: AFAIK Global Elite starts at about 1600-1700 elo, theres a lot of room above that
Cool. As a Legendary Eagle Master I didn't even know this. I assume that is like the top 2.5% or something? I would agree with the initial statement of the article, though: Watching "real" competitive players just seems like magic and I feel like average at best, albeit apparently (as I just learned) being in the top 5% or better. Same goes for basically anything else I am "good" at, even with work. There's just always so many people being so much better ...