I try not to view things as problems to be solved, so much as conversations to be had.
Well, I could believe that if you didn't use phrases like "fear of the new", "the race/class de jure restrictions remained", "instead of moving away from the Gygaxian model of racial essentialism, we move back toward it", and so forth. All of that language suggests that there is a problem, and in particular a problem you have with what you perceive as the way D&D is "de facto" played.
The problem I have is that you assume a problem exists without well defining it or even questioning hard whether it is a problem, and more importantly, having assumed a problem you offer no practical solution.
I suppose you leave your thesis statement to the end, which is fine, but if it is your thesis statement, I'm not at all sure what it means:
"My only cautionary note is that it is easy to fall into the idea that lore and mechanics, when it comes to race/class combinations, becomes the exact type of racial essentialism that we should try to avoid."
I suspect you did not mean for this sentence to mean what it literally means and you need to rewrite it. Taken literally, this sentence cautions you from taking the stance that you took in the essay. That is to say the sentence literally says that we should not fall into the idea that lore and mechanics is a type of racial essentialism that we should try to avoid. I agree, but then that is at odds with your essay.
You have not demonstrated that what you call racial essentialism is bad, nor have you in any way shown that if it is bad, that it is de facto, or that if it is de facto that this is a result of the rules, or that if it is a result of the rules you haven't proposed any fix to that problem.
If you consider this a conversation, what do you want to talk about? Conversations are usually prompted by questions, and not thesis statements. I'm not seeing you asking a lot of questions.
Personally, I think Paladins add a lot to the game. I agree with you about Gnomes, but not with your solution. I don't find either of those 'problems' to have simple or easy to understand solutions.
The problem solver doesn't sell his solution to the consumer, he sells the consumer to his solution.
PS: I have no idea what that means either.