It’s hard to explain but, speaking and learning another language outside of an official classroom setting is (somewhat) demonized in the elementary and middle school (Pre K - 8th Grade) portion of the average American education system. It’s all fine and dandy if you pick up another language by learning it at school but it’s looked down upon if you learn it outside of school. For multilingualism and bilingualism, it’s a “what’s classy if you’re rich but trashy if you’re poor” situation where there is a double standard on when, with whom, or how you learn multiple languages. The problem is if a working class person, Person of Color, or speaker or a non-prestige language is a multilingual speaker they’re seen as uneducated, but if a foreign language or second language is learnt in school in particular among affluent communities, especially if it’s a language arbitrarily seen as prestigious and not attached to a visibly underserved/neglected ethnic minority community in the region, the person who learnt such language is seen as educated/sophisticated.

Due to how ESL in the U.S. is set up, K-12 schools are forced to consider students who have or are perceived to have someone in their household who speaks a language other than English to automatically be non-fluent speakers of English even if they’re actually fluent English speakers or even monolingual English speakers. So this ends up convincing parents and children to hide their bilingualism/multilingualism until they reach high school or even graduate compulsory education in some cases while in others, it pressures parents to not teach their kids another language (unless it’s in an official classroom setting). Testing out of ESL as a fluent English speaker is difficult if you’re a terrible test taker (have yet to develop test taking skills) or if you’re not reading/writing at or in most cases above an idealized grade level even though your non-ESL monolingual English speaker peers are equally not meeting that same standard. People in this camp should actually be in remedial/extra help reading/writing classes alongside their fluent English speaking peers as opposed to English Language Learner classes. Also underfunded schools and even well-funded but neglectful and/or improperly trained schools, wrongfully put non-English speakers/non-fluent English speakers in special needs classes for those with learning disabilities, intellectual disabilities, or speech impediments instead of the English Language Learner (ESL) classes they actually need because some decision-makers can’t tell the difference (and in some cases vice versa).

There are about between 350 to 430 languages spoken in the United States and around 450 languages in Canada. But, the number of / percentage of people who can speak more than one language in the United States is definitely an undercount (underestimate) because the U.S. Census only counts what languages people speak at home in a household, and not other languages spoken in a professional, academic, recreational, or non-household setting outside the home (it doesn’t actually ask how many languages you speak total and what those languages are, it asks what language is spoken at home not accounting for whether they speak with several languages at home).