Leaving aside the "high rank" rant.
Sure they are annoying but there are quite a few ways of countering them.
This game is obviously not about skill, but even with that, and even after Siege removal, this game still has huge gaps of "skill" (more centered on knowledge than micro nowadays) creating an abysmal difference between casual and regular/dedicated players, and also leaving an almost as big gap within the regular/dedicated/veteran players.
High skill now is more about strategy and knowledge of the game, allowing to adapt, counter, and prevent pretty much everything. Micro is still important but not that much.
Anyhow, they are going to be changed soon:
The current plan is to significantly lower their health, speed, and the number that spawn.
In addition, we will be fixing bugs that cause them to spawn even when flipped of the map.
Lastly, we will be adding more systems to allow you to notice firelings by adding new sounds and explosion delays.
These changes make them FAR less threatening.Source