The modern .NET runtime can get devirtualize interface calls and eliminate temporary object allocations in some scenarios. It's a bit of a black box - who knows when it actually works? - but still, it's a nice boost here and there.
I assume it's not a black box anymore, but maybe that's a non-free lang extension? I had assumed linq was part of .net core these days, but I haven't gotten around to checking (10+ years since I've had a serious .net project)
