Hmm. You seem to have overlooked the second column labeled "Including second language speakers". The breakdown

No, I did not.

In my second paragraph, I mention 50E6 current students. Many of them will take spanish lessons. All of them reside in the US. Let's say only 50% does that, we'll be talking 25E6 with english as 2nd language. I also mention a reference to some 41E6 hispanic US residents. Those add up to 66E6 (or a total of 483E6 vs 503E6, a difference of 20E6 or ~4%.

But according to the same source, that is precisely the fastest growing minority in the US.

I would say that a difference on less than 4% is dubiously decisive with this kind of sources / metrics. That is why I granted the point for a few years :)

Let's reopen the debate in a few years, if this is so important a question. :)