Well, for starters, it's a greentext, so who knows how genuine it is, right? Most of the points listed are either subjective or citation needed fodder. However, maybe there's one fact I can bring to the table:

ASP.NET's benchmark performance ranked 16th in Round 22 of the TechEmpower Web Framework Benchmarks, ranking below solutions written in Rust, C, Java, and JS. C# has advantages over each of those languages and frameworks in exchange for the relative loss in performance. Rust and C are much lower level. Java's syntax is generally considered to lag behind C#'s at this point. JS's disadvantages could fill a whole post of their own. C# and .NET have their own disadvantages (such as relatively fewer libraries available) as you've pointed out in this thread and another in this post, but when you take into consideration the relatively high performance while being a strongly-typed higher-level language with plenty of nice QoL features, you might be able to see why it could be attractive to a specific slice of professionals.