Whilst i can agree with you there, i have to say, i think it is right if a person wants to say, they are done, as long as their reasons are valid.
You see, complaining, saying your piece and crying rivers is, in most situations used to improve the game. Mostly.
People are leaving because of the state of the game, i too am one of those players that sometimes thinks, this game is ■■■■, i am off. But, i just have a break, come back in a month or in Eight.
I am a Horde player, i have been saying since Gears of War 4 that if you make a Class system, then that is what you make. For example, Gears of War 4 Horde, the Scout and Engineer should have been important characters in the game, indespensable, the Scout collects Energy and dumps it, is and only character to collect Energy. The Engineer is the only one to build and repair, incidently only one to move the Fabricator too, and an option to lock down Fortifications. These characters were not used to their full potential, and were actually devalued.
In Gears 5 Horde, the Engineer has had an upgrade, but it is not enough, the same issue is there again, the Engineer is devalued, slightly, and worse still, Horde is built around Jack and the Forge, Energy has been stupidified and Taps created to fill in the gaps. The Scout has been devalued as a Scout.
Horde has been ruined, but i will not leave, so instead i will have breaks, use harsh language and eventually return.
Critique the game, complain, or it will never be fixed. Yeah, these post can be annoying, but needed.