I think people should learn the language they are comfortable with and does the job. There's a lot of talk over the internet about this language being superior to the other and vice versa. These people talk too much you may wonder if they really have time to code. Just code and create with that language that you use and learn, shift to another language if you are looking for a certain functionality, not because of the popularity contests.
1. If you are asking for a startup trending language. Python is famous for its easiness and machine learning mechanics.
3. On the other hand, the mortal language of all the times is C/C++ as both are good for high-performance products I.e embedded systems or AAA games 🎯.