Why is D unpopular?

[Siarhei Siamashka]

On Thursday, 19 May 2022 at 00:29:46 UTC, Walter Bright wrote:
> I did a quick look at D's undefined behavior, and nearly all of 
> it is disallowed in @safe code.
>
> It's not 100%, but we're in a strong position.

Regarding safety and avoiding various sources of undefined 
behavior. Do you agree that "Implementation Defined: The built-in 
associative arrays do not preserve the order of the keys inserted 
into the array. In particular, in a foreach loop the order in 
which the elements are iterated is typically unspecified." from 
https://dlang.org/spec/hash-map.html can be a source of bugs in 
the user code?

Also I wonder about the motivation to have 
"SwapStrategy.unstable" set as the default for 
https://dlang.org/phobos/std_algorithm_sorting.html#sort ? If 
somebody actually wants a stable sort, but just happens to forget 
to override the default in some part of their code, then this 
mistake may cost many hours spent on debugging/troubleshooting.