This is somewhat pertinent because evil monsters is part of the heritage of D&D.
I have tried to avoid wading into any of these issues on the multiple threads, but I wanted to touch on this. I am not a huge fan of the word heritage. In many Southern areas of the United States, you will often see or hear the phrase, "Heritage not hate" used as a defense to overt symbols of racism. And it's always the same- for example, no one discusses the need for amazing BBQ, or fine bourbon, or the proper way to make cornbread with a need to say that its heritage and not hate ... but you start talking about flags, or how awesome plantations are, and guess what? There is that phrase again.
The reason I bring that up is that "heritage" cannot be used to shortcut uncomfortable conversations, or to elide over unpleasant truths. When I see that the OP framed the debate as one between "heritage" and "inclusivity" it therefore had unfortunate resonance with me.
Heritage and tradition can be, and are, wonderful things. The rituals that we go through, that we pass along, from one generation to the next can be a source of comfort and bonding. All of us have these rituals that we go through in our lives; things as simple and comforting as a favorite movie that we watch every holiday with our families, or a tradition of having a family meal at a certain restaurant to celebrate. These rituals can provide comfort and structure to our lives, even at the most dire (the release of the funeral and wake being a good example).
It's the same with TTRPGs. Many of us are familiar with the rituals ... with the heritage of the game writ small (sitting around a table, rolling dice) or large (kobolds, mind flayers, elves, fighters, six abilities, etc.). We get comfort from that, and we pass that on to a new generation. Some things change, some stay the same.
But these rituals, and this heritage, should never a substitute for inclusivity. I have to re-evalutate things that I don't like to think about.
Some things came easily to me. I often use the example of the ability caps and "cheesecake" art in early D&D because it exemplifies structural misogyny. I didn't consider it
at the time, but in retrospect it is glaringly obvious how it both reflected the gender norms of the time and reified them; I could not image a teenage girl today feeling comfortable playing an all-male game with that kind of art and the expectation inherent in it, and while some did at the time, I now understand how it was more difficult for them in ways that I did not understand. And I am happy that it changed.
And I also see that there have been racially-charged elements in the game; some of it is unavoidable given the antecedent sources. There are times when I want to argue with people about things; after all, problematic things like Oriental Adventures stirred a love of all things Asian in me and made me look to the source material for a much deeper and more nuanced dive than if I had never read it. In effect, I became more broad-minded because of it. It's the same with Deities and Demigods; with all due respect to Jim Ward who had a thankless task, there are some serious errors in it ... but I would not have bothered to learn more had I not had the initial exposure. One of my best friends that I grew up playing with went on to get a PhD in history, primarily because of our shared love of what we had been learning that was spurred by D&D.
...but, that's not an excuse to avoid making things better. And I have to admit, I understand what you are saying. Part of me, the part that grew up playing D&D and slaughtering orcs and kobolds and goblins (oh my!) cannot understand the current ruckus. I do understand the "orc" issue, but I am also worried about the categorical attempts to get rid of all humanoid creatures that are "default evil." Because if you don't know that ALL orcs are evil, then how can you slaughter them without worrying about it?
And maybe that's the issue? I don't know. I know that lately I've been a lot less comfortable with humanoid monsters as critters to be slaughtered, as if they were extras in Commando (Ah-nahld 80s movie). I think that there are people, a new generation, that are playing D&D and I might need to listen to what they are saying. It doesn't mean that they are right about this, or about everything, but I am less certain that I am right, and more convinced that I need to hear other people out.