On the finance part, I think it's complex, in particular relative to who. For instance, immigrants will massively be bilingual in general. We could argue there

On the finance part, I think it's complex, in particular relative to who. For instance, immigrants will massively be bilingual in general. We could argue there are in a better financial and educational position than those who couldn't immigrate in the first place, but then relative to the country they live, they can be on bottom of the social ladder. On the parrallel with studying other subjects, I think it rings true, the only difference would be that bilingualism can be "forced" upon children by circumstances or environment, where math or instruments usually come later and/or on a choice basis.