They're pushing hard in that direction with https://dotnet.microsoft.com/en-us/apps/aspnet/web-apps/blaz...
I don't think we've heard the last word yet.
JS/node are no competitors to .NET, not even close, only in the minds of script kiddies.
I only done desktop .Net apps so I can't judge, but even if I love the language and the standard library in .Net I would never had considered using it on a server if I had a choice, not because of quality but because of Microsoft bad treatment of the licenses an, the FUD and how they handled it. They managed to drag this platform down that js and node has probably more users and mind-share, they even had to "port "C#" and create TypeScript.
Btw, i did not implied anything about node or npm quality, someone that worked with both seriously in recent years might add their thoughts (so I am not a node fan just a C# lower disappointed on MS behavior).
I personally was a big fan of C# and I can't forgive MS stupidity , because of the Windows Team a good language and platform was sabotaged, as I said it could have been a worthy competitor to JS/node especially in the past when JS was shit and even now where npm is filled with leftPads and colorRed packages.