Oh, I completely agree on the problem, and I think any technological solution to that problem will require NLP (perhaps tautologically so). But to my mind, the

Oh, I completely agree on the problem, and I think any technological solution to that problem will require NLP (perhaps tautologically so). But to my mind, the open questions are (a) what does that mean specifically? and (b) is a tool like that compelling enough to motivate a venture-backed startup in 2022? To expand on (a), I think a Young Lady's Illustrated Primer [1] that generates interesting level-appropriate content on the fly is extremely compelling, and it's aligned pedagogically with principles like extensive reading [2]. Leaving aside its feasibility, such a primer is clearly providing NLP-augmented language learning --- but at the same time, it's a very different vision from what OP describes. More broadly, tools more aligned with communicative language teaching (CLT) would almost certainly rely on NLP without reaching too deeply for dictionaries, exercises, spaced repetition, and grammatical explanations, all of which seem to be in scope for OP. There's a lot of room here, which is why I maintain that the critical question is a simple one: is OP's specific solution to the problem something people want? [1]: https://notes.andymatuschak.org/The_Young_Lady%E2%80%99s_Illustrated_Primer https://notes.andymatuschak.org/The_Young_Lady%E2%80%99s_Ill... [2]: https://erfoundation.org/wordpress/ https://erfoundation.org/wordpress/