Guys, does it make sense to switch from C# to F#? I mean, C# adds more and more F# features each year and I think they will probably be on a par with F# in 3-4 years. By the way, native immutable records will be added to C# next week in C# 9.
On the features you mention while some of those features are being added to C# (and not all of them are planned to) from what I've seen they often aren't as powerful/useful as the F# version, are not as consistent/concise due to legacy syntax or don't interact with other features as well. F# is also taking C# features so its not like you will be left behind either (e.g. Span). For me more importantly the underlying defaults are a feature that can't be ported which IMO F# wins here.
C# is a fine OO language having worked with both extensively, just F# IMO is slightly better with less ceremony than typical C# code. Is it worth switching? It depends on your problem and where your starting from. In this case they are switching from OCAml so F# probably makes more sense. If your starting from a clean state it all depends tbh what you find easier to learn - IMO many JS/Python/Go/etc programmers if trying .NET Core might find F# easier than moving to C#/Java from their own personal preferences - its often called a "typed Python" by users. For C# users probably less so; but learning it might change your C# code style for the better.