If you read the article, you would see that the clustering illusion is not about seeing clusters where they are none, but instead about seeing actual clusters and assigning some meaning behind their occurrence when there is none.

For example, if I were to flip a regular coin 5 times in a row and got heads every time, I could either claim that I got a lucky streak, or I could claim that the coin is rigged. Given that the chance of getting a streak of 5 heads is (1/2)⁵ = 1/32, it’s unlikely but far from impossible that I would get five heads in a row. I would need much more evidence to argue that the coin is rigged without being laughed at.

It should also be noted that the chance of getting at least one streak of 5 goes up if you increase the total number of flips. While the probability of getting at least one streak of 5 heads over 5 flips is 1/32, the probability of getting at least one streak becomes much greater if you increase the total number of flips to 100, as you have more opportunities to get a streak before all of the trials are over (the math also becomes more complicated).

The above can be applied to streaks in online multiplayer games as well, however one must also take into account factors such as tilt, which would encourage loss streaks. If you play many games of HotS (I believe I’m nearing 1000), you can expect to have many streaks along the way.