There was a talk at the time, but I can't find the video: http://jaoo.dk/aarhus2007/presentation/Using+LINQ+to+SQL+to+....
Basically, it was a way to cleanly plug SQL queries into C# code.
It used this sort of ordering (where the constraints come after the thing being constrained); it needed to do so for IntelliSense to work.
Of course there's EF Core too.
Also, there are fun things that support Linq syntax for non-ORM uses, too, such as System.Reactive.Linq and LanguageExt: https://github.com/louthy/language-ext/wiki/How-to-deal-with...