I have interest in these languages because, in general, I have high appreciation for simple solutions to complex problems. I find very interesting how they solve different challenges.

I just learn a bit about them, but do not learn to speak, at least not enough to have the simplest conversation. But I understand how you could get more hooked into it and learn it and spend many hours with your toy language.

From all the unuseful hobbies people have, I do not think learning artificial languages is one of the worse.