> - Super fast

For all it's other features, I'm really not sure I'd call .net fast. It's got half decent speed, but it's not "woah that's fast"

> - C# and F# are constantly updated in coherently

By which you mean C# gets new features every year, and F# gets thrown enough tidbits to keep it looking alive?

> By which you mean C# gets new features every year, and F# gets thrown enough tidbits to keep it looking alive?

Every new C# version makes interoperability more of a pain. The C# team have no interest in compatibility with F# and will NIH stuff that could've been taken from F# libraries. One of the biggest pain points for interop is tasks, for which there are half a dozen libraries for F# and everyone uses a different one. There's been an open issue for F# to have native task support for years, but progress is slow.

Just Google around for techempower benchmarks for speed. You don't have to rely on some random opinion on the web.

C# gets more features every year than F# because C# is still trying to catch up to F# 1.0. F# 5 got good updates this round (https://devblogs.microsoft.com/dotnet/f-5-update-for-august/)