Are you saying you tried rust in 2013 and found it unsuitable? I think it was a pretty different thing back then. Though obviously that doesn’t mean D isn’t a great choice.
Keep in mind that Rust 1.0 was released in early 2015, and it's not like they were making major changes right up to that release date. I haven't followed it recently, but I doubt it was meaningfully different from the 1.0 release in terms of learning curve.
Here's a blog post from the same year that proposed removing the garbage collector.
https://pcwalton.github.io/_posts/2013-06-02-removing-garbag...
Also, since 2018 with non-lexical lifetimes and some nice error handling improvements, Rust now tends to be more friendly/ergonomic than 1.0.