How do you differentiate between a character "written for the sake of checking a diversity box", a poorly-written diverse character, and a "random fact of the world"? It's a fictional world. Nothing is random. It's all creative decisions made by a team of writers and producers.
I don't think shoehorning in of diverse identities and character backgrounds is good representation or good art, and I completely agree with your point there.
But I don't think that the people driving the current backlash bother to make those distinctions.
What I see is a lot of outrage being stoked by people using the (updated) language and tactics of gamergate, and I don't think the result of that will be "better representation".
I think the result will be devs being harrassed and pushed out of an already brutal industry.
Add on top of that that the games industry has laid off TENS OF THOUSANDS of devs in the last three or four years.
I know a lot of talented people who are no longer working as devs, or who have been job searching for months.
Of course this doesn't mean that the studios still producing games have narrowed their scopes, they just dump more work on the survivors.
And "woke DEI SJW snowflake game dev" is far from the only thing making games worse, it's just what a lot of gamers can easily identify as a problem.
By the time I left, my last industry job had been reduced to what felt like manning the slop hose of mtx store items made by overseas outsource studios producing soulless trash under fuck-knows-what kind of nightmare working conditions.
We started seeing more diversity in games because devs are diverse and wanted to see themselves and their friends in their art.
The problem has never been queer or black characters in games. It is, and always has been, the prioritizing of profit over quality craft.