EDIT: Places I've seen this include Canada (English and French) and Southern California (English and Spanish).
I do not believe California has any mandates on bilingual product labeling. A very cursory Google search found nothing beyond an article about them
considering requiring it on prescription medicines.
Regardless, I chuckle, because here in Switzerland, products must be labeled in at least one of the three official languages, but because of logistics simplicity, practically everything is labeled in all three, and increasingly in English as well. And with German and French (two languages with famously long text lengths) being among those three, this often leads to comically inefficient layouts. :p
"one" is a singular subject
Similar to how "they" and "them" are plural.
At least most of the time.
These days.
The use of singular “they” (and the inflected forms:
them, their, theirs and
themselves) in English goes back to the 14th century, only a century after the emergence of the plural “they” in the language to begin with!
Yes, the expansion of singular “they” to a deliberate “I identify as ‘they/them’” usage is new, but
grammatically speaking, it’s absolutely established, and the least-disruptive of any of the alternatives. Any of the alternatives would be significantly harder to get used to, which is likely why those alternatives haven’t caught on, while they/them has.