.NET has been around for two decades. It's a well established technology with plenty of resources, documentation and libraries and frameworks. I guess these are in part the reason it's still thriving.
You're thinking about .NET Framework reading your opinions on it, .NET (Microsoft is terrible at naming) is the "newest" standard and it's fully open source and cross platform. They removed Windows only APIs and embraced the open source way.
While Microsoft is indeed full of shit they did a great move with .NET in the last 10 years.
You don't even need Visual Studio, I use Rider for instance and I love it! I cannot stand Visual Studio either, mostly because I hate its UI/UX.
At the end of the day is matter of preferences, I like .NET and C# and I work with these technologies daily for instance.