https://www.wildernesslabs.co/
https://nikolayk.medium.com/getting-started-with-unity-dots-...
Had Remedy experiment worked out, maybe DOTS would be using D instead of having their own compiler infrastructure for HPC#.
Nor Java even,
https://www.ptc.com/en/products/developer-tools/perc
https://www.aicas.com/wp/products-services/jamaicavm/
The main reasons are not having a big name company that would push D no matter what, and lack of focus where D should aim for.
You can ensure your D code doesn't use the GC by adding the `@nogc` attribute.
But really, all this concern about the GC is misplaced. It's just another tool available. You can use it in D, or use RAII, or your own allocation system. It's your choice as a D programmer.
I am giving this analogy since Walter has a degree in mechanical engineering and he has correctly made the GC a default in D but not mandatory, but the choice somehow is not popular in the software industry.