[Mordisquitos]

>Translating is the only option for the vast majority of people.

The key word here being 'option'.

>After 25 you can’t really learn new languages without considerable investment and effort.

And by enabling this translation by default, without any obvious way to disable it, they are also making it harder for < 25 year-olds to be exposed to other languages, which will itself make it harder for them to learn them. For instance, consider the effect of TV and film dubbing on Spain's proficiency in English[0]:

    «Spain and Portugal share many geographical and cultural traits. But the number of Spanish speakers is double that of Portuguese speakers. Again, maybe in part because of this, Portugal uses subtitling while in Spain television is dubbed. And, as a result, Portugal’s results in the TOEFL exams are much better than Spain’s.»

[0] https://www.gwern.net/docs/culture/2018-micola.pdf