I came up with the foundational structure and concepts for my primary campaign when I was in high school, long ago in the late 20th century. Since then I've added to it, adjusted, had time pass as campaigns came and went. The characters in the campaigns saw and either helped or were helpless to stop the rise and fall of kingdoms all while changing the course of the world in ways I could not have ever anticipated. What the characters do and the players have chosen to pursue continues to influence that world.
If someone doesn't want a world rich in history and lore to discover then, like a lot of players, you can ignore most of it and I'm not going to bore you with details you aren't interested in. It just all becomes foundational stuff for me as a DM. Along the same lines if a different DM wants a kitchen sink campaign with little built in lore or just uses FR or they create a new world for each campaign I might be interested in playing. But no one has the high ground, moral or otherwise because their preference differs.
One thing has remained consistent in my campaign world. I have a relatively small number of intelligent humanoids running around, both playable races and not. This is purely my preference, I want the world to feel "real" in a way that I just won't get if I allow dozens of different species. To me if there are dozens of species running around there is no way to give them all unique feel, they almost all become human in all but name only with rubber prosthetics. There may be thematic elements, but those thematic elements could apply to any species. In any campaign they're still just generally stereotypes of human nature boiled down into a few sentences with exceptions for specific individuals. But at least in my campaign I have a history, a place in my world for all the species.
The species someone plays is just someone else's made up stereotype of human existence and is a tiny fraction of what that character is and will become. Is there anything truly unique to a dragonborn other than scaly skin that couldn't be replicated in a human?
Funny thing is I tell people that if they want to play something not on my curated list they can always ask. The last time that happened was in my 4e campaign 15ish years ago. In that case we were able to come to a compromise, the character was not human and few knew they were not. There was no dimensional portal or a lab accident. They didn't just declare they were running a species not on my list. We did it by discussing options and coming up with something that we both agreed upon and we both gave a little. Radical.