It’s not underrated, it’s hated :-)
It has a stigma attached to it, simply because it was invented by the Evil World Domination that is known as Microsoft, but people love golang because it was made by that nice cuddly cute company known as Google….
C# is a very, very powerful server side and general development language, but so many people (especially open source diehards) have such a hatred for Microsoft, that they denounce it as an inferior language, they cast its aspirations into the pits of anarthy, and try to persuade you that every other language in the world is better.
The really funny part about all this is that Typescript is currently seeing a very large popularity rise at the moment, and (cough).. that too is a Microsoft Language, but because it makes folks’ job so easy, and there almost zero friction to get started with it, people overlook that aspect of things.
A large amount of folks where C# is concerned, also still don’t believe that C# is now as cross platform as it is, many folks still think that it’s native on windows, and that code you write will be restricted to the windows (and Thus) microsoft platforms.
The ONLY way this is going to change, is if people just go ahead and adopt/use it anyway, then show the nay-sayers afterwardswhat was done.
Source : https://www.quora.com/Why-is-C-so-underrated-when-you-can-create-apps-for-almost-any-platform-with-it