Let's rephrase the question. Why can't I excel at math? Am I stupid?

If not everybody's supposed to excel at math, why would we lower the bar for language? Of course everybody can learn a language, but results will vary from "two beers please" to fluency. I'm not good at math. Why should I?

There is nothing wrong in adopting a the-sky's-the-limit or a nothing-is-impossible-if-you-set-your-mind-to-it attitude, but I think best learning comes when we set realistic goals in our learning journeys.

Questions around language learning end up in a series of I-can-do-it-and-so-can-youassociation fallacies that language learners should beware of.

While children learn any language organically, adults learn a L2 in a more systematic way, hence the individual differences.