Oh my this is so true:
* I waited for Duolingo to support Mongolian for years, and in one evening, created my own DuoMongo https://github.com/matusfaro/DuoMongo
* I wanted an LLM to mock up a server to speak arbitrary network protocols across any layer (e.g. http/tcp/bgp/snmp/arp) for protocol development/testing/cybersecurity and I got it: https://smotanacom.github.io/netget/
* I wanted a way to inspect/route LLM calls coming from my laptop, something like OpenRouter, but locally running, so I built LocalRouter: https://localrouter.ai/
No one is using these, but I love them!
Also it allows me to prototype so quickly, currently had an idea on a Language Server Protocol (LSP) that compiles English language into a set of software requirements (Intermediary Results) and to generate code and tests against those reqs.
Did you want to learn Mongolian or did you want to play a video game where you pretended to learn Mongolian. Because if it was the former, plenty of resources have been available for you for years. You could have walked into your local bookstore and bought a textbook, hired a tutor on italki, downloaded an anki deck, listened to MNB broadcasts etc. etc.
I think LLMs are pretty similar to DuoLingo. It is a tool that makes you feel like you have accomplished something without you putting in the work you need to actually accomplish anything. Worse still, you still need to put in the time. So in effect you end up wasting a bunch of time without learning anything new. These machines, are dopamine generators, kind of like cigarettes, or slot machines.
My anecdata is that both Duolingo and LLMs are useful in learning. Yes, you have to put in the work.
Seeing the usual HN hate on Duolingo specifically, I wonder whether it's blind. I might have missed scientific research about it causing cancer.
Responding with my own anecdata: Duolingo is not bad, but better options exist, in with a gap in quality and quantity that you might as well just use those (admittedly, I have been learning Spanish and Japanese, languages that have a lot more resources than Mongolian).
Speaking with anyone who has intensively learnt languages, FSRS is the best way to remember vocabulary (you will need a separate source to actually learn it). And I've found that books often offer more structured practice and introduction. After you've outgrown books, picking up words from real conversations / media is much faster and makes you more likely to actually remember them.
And for Duolingo, there are many things to nitpick about. The obsessive gamification, the hearts (and the current energy) system that prioritizes getting answers correct by guesswork and cheating or being limited to a few minutes a day, the company firing chunks of it's core translation and language staff.
Duolingo is more than adequate, however, if you plan to do 5 min / day and just want to keep a streak going. I have seen people who have gotten real results from it too.