Epic decided that stretching resolutions will no longer be allowed in the new competitive game mode, Arena, or tournaments. This has made pro players angry because for the past year many have switched to 4:3 or 5:3 aspect ratios to, in a way, cheat the game.
Some say they do it because it feels better or they personally prefer it that way, but in reality, the reason they do it is for increasing the vertical field-of-view. Vertical FOV is important during build battles because it helps in keeping track of your opponent as you build on top of each other.
It is also fair to note that this isn’t something you can do in the game settings, you have to edit a configuration file to get the desired results.
A Reddit user made a great post comparing the difference in the vertical and horizontal field of view of different aspect ratios.
The pro players are mad because in previous tournaments this tactic was allowed and they practiced using those settings. Ninja went so far as to say on Twitter that his practice is now wasted due to the change. Myth agreed that the execution was very bad and in general they are unhappy with the way Epic runs competitive gameplay.
This also comes after a controversial reversion of certain gameplay mechanics that were intended to increase the speed of gameplay. The changes did exactly what they were supposed to, but Epic then decided that they made the game less welcoming to new players and as such removed them from the normal queue, but kept it in Arena.
The more casual part of the fanbase made comments saying that pro players are dancing on a very thin line between what is considered acceptable and unfair exploits just to gain the tiniest possible advantage over other players and as such, they shouldn’t complain if Epic decides that something is crossing that line.