I worked very little with D, and a lot more with Rust. I cannot really speak to the qualities of D because, by and large, I dealt with a very few instances of it, and only at the interface level (mostly writing in another language). But, in terms of fame and popularity -- Rust developers and backers put a ton of effort into promoting the language. There were times when every other week there would be an article in some popular tech. media source from all kinds of "big names" about how Rust is superior to something (usually C++). There were massive efforts made to create a self-sustained community of Rust-evangelists who'd go and spread the word to the heathens...

I haven't been around to witness the birth of D and don't remember if it had any kind of adoption campaign, but from what I can tell, even if it had a campaign, it didn't succeed.

Now, here's another example from the same category of languages: Ada (esp. with Spark). I'm not very knowledgeable about it, but from the little I know, there are a lot of good reasons to prefer Spark over Rust. At least, on engineering merits, they should be roughly equivalent. But, in terms of popularity, Rust beats Spark by a lot.

Why? Excitement doesn't always follow correctness or even "goodness" (whatever that means in context), even if we'd like it to. Fashion and marketing matter more when it comes to excitement.