Iirc, back when I was interested in learning Esperanto, one of the criticisms I saw was that it's very Eurocentric in its design. It strives to be a "universal language" but is very obviously rooted in Romance language. However, conversely, I remember seeing the argument that learning Esperanto for a second language is comparable to learning the recorder for music: it's not so much that you will use the skill in Esperanto, but more you will use the skill in language-learning to more easily learn other languages.
Personally, I think Esperanto is pretty neat, especially conceptually, but probably not too practical unless you're involved in the Esperanto movement and committed to it. I believe there are people raised to speak it natively, and there is a sizable international community. It could still catch on, given the right spotlight.