1. Because I like engineering more than programming. If a problem is best solved by, say, a mechanical system then I will do that instead. But even where programming provides the best solution, not all ecosystems are equal. If I have a problem best solved by, say, AI/ML, it is often impractical to avoid Python. Likewise, if I have a problem best solved in the web domain, it is often impractical to avoid Javsacript. SQL where databases are the best solution. So on and so forth.
2. Because I like to learn. In my younger days, I found a lot of value in exploring the different ways people live. In fairness, I've toured the programming world enough by now that I am less compelled to keep go on "programming language vacations" – at some point you start to feel like you've seen it all, but believe I would be a far worse programmer today had I not been able to take ideas from a wide range of different cultures over the years. There are some good ideas out there that don't seem to ever gain mass adoption outside of their originating ecosystem.
2. Because I like to learn. In my younger days, I found a lot of value in exploring the different ways people live. In fairness, I've toured the programming world enough by now that I am less compelled to keep go on "programming language vacations" – at some point you start to feel like you've seen it all, but believe I would be a far worse programmer today had I not been able to take ideas from a wide range of different cultures over the years. There are some good ideas out there that don't seem to ever gain mass adoption outside of their originating ecosystem.