Ask HN: How was your experience moving from one tech ecosystem to another?

I would like to hear personal experiences of moving from one ecosystem to another after several years of experience.

For e.g. after working for more than 10 years in JVM ecosystem, you moved into a Python and how did that change your career ? When you look back do you think it was a good move? Would you do it again ? What are the pros and cons of doing it? What are the risks ?