Тут JetBrains крутейшую инфографику выкатили по различным платформам. Позиции .NET Core приятно радуют!
https://www.jetbrains.com/research/devecosystem-2018/csharp/
https://www.jetbrains.com/research/devecosystem-2018/csharp/
JetBrains
C# in 2018 - The State of Developer Ecosystem by JetBrains
Over 1000+ developers share their insights on modern C# programming. Keep up with the most relevant technologies and frameworks in this infographic!