As far as .Net's future as illustrated, Android is not the preferred target for most mobile developers; iOS is, and currently the best cross platform runtime is based on mono/.net. Time will tell if cross platform server software programming catches on (my hunch is that it will with more mature frameworks). Kestrel and .net core 5 are a huge assault on java on the server, and warrant attention from oracle.

As far as the IDE's, I've used both and can say that I vastly prefer Visual Studio paired with ReSharper (the R# in the previous comment). This is the first comment I've seen in a public forum, actually, that says that VS is not better than IntelliJ.