Is that something you are willing to bet a major architectural decision on and/or your career?
I’ve been a Microsoft developer for over 20 years and a .Net developer for over 10. Even though I don’t see .Net “dying”, it’s also not a major growth opportunity.
Java is definitely not doing well compared to .Net even though it is open source - because of the mismanagement of Oracle. I see dart going down the same road.
As much as I prefer .Net to the JavaScript ecosystem, I am tying my horse to it. I’m focusing my attention on everything JavaScript over the next year (yes it makes me sad).
Until four months ago, I had never touched Python. But the more I got into AWS, the more I realized that the ecosystem around AWS and Python seemed to be the strongest. So Python it was.