Counter-Strike: Global Offensive's rank distribution is set in stone, and that means it may be harder for some players to rank up.
In 2015, Valve recognized there was an issue in the way that players were ranked in CSGO. Their data showed that there were many more players populating the higher ranks than there were the lower ones. In response, Valve instituted one of the most controversial changes to CSGO's ranking system in the game's history. CSGO's rank distribution went from a curve that was heavy at the top to the bell-shaped curve that exists today.
The above image shows the rank distribution prior to Valve's changes. When Valve shuffled the ranks, the resulting deranking of many players into lower skill groups evened out the chart, but it also did something else. In order to keep CSGO's rank distribution looking like the image below, Valve had to institute some sort of cap to prevent large shifts of players in either direction.
This is why it is sometimes so difficult for players to rank up in CSGO. Not only do players have to get better and improve their skills to beat the players below them, they might actually have to wait until someone above them gets worse.
The only way for CSGO to keep such a consistant curve in its rankings is to cap the amount of players at each rank. League of Legends does something similar, with promotion and demotion games and an easily understood leaderboard where players can see exactly how many players are both above and below them in their division.
In CSGO, this happens entirely behind the scenes. It explains the many soical media posts that claim players have gone on ridiculous win-streaks while fragging at the top of their teams, but still don't increase in rank. Simply put, if the people above them are winning, it may be harder for them to rank up.
There are tricks to ranking up, but none of them have to do with gaming Valve's ranked system. Playing at different times of the day, for example, can often impact who a player plays against. A match that takes place in the middle of a school day might have older and more casual players in it than one that takes place on a Saturday afternoon.
Ultimately, CSGO's ranking distribution in 2020 looks just about the same as it did after the infamous ranking adjustment in 2015. But the way to rank up in CSGO is still the same as it was back then. Players just have to consistently play well.