Keep in mind If one examines anything in great detail you can find problems. For example the 50/50 coin flip numbers are slightly off when applying it in real life. Flipping a coin has a large number of variables that move the results away from a perfect 50/50. A nickle has about a 1/6000 chance to land on its side. Furthermore there is a small tendency for a coin when flipped by a human to land on its original up face (as high as 51/49!).
But the important thing for Gems players to take away from Salty’s post is that each flip/chest/rainbow is INDEPENDENT of the previous.
Honestly, this may have been better off as a FAQ entry than a forum post. The original post - “a 1/100 chance for A Thing does not mean that you’ll get The Thing if you try 100 times” - is a perfectly fine explanation of random chance and independent events.
All of the followup posts about how statistics and RNG are very complicated are true, but also completely irrelevant to the original point. The discussion drowned the message.
If this is correct, the devs are doing themselves a huge dis-service. Perceptions of fairness are usually based on whether things happen as people expect them to happen. For example from the description you expect Fizzbang to explode 50% of the time. From play you find that it explodes more like 75% of the time. This leads you to distrust the game. When you later run into a bad streak and fail to get any mythics after opening a large number of gem/VIP chests, you start wondering if it is bad luck or if it is because there is something wrong with the game.
and 
part is; we know this is true to a certain degree…