Or maybe you’re wrong. I think everyone here is missing the point. If the choice is between 5 minutes a day of Duolingo and _no_ language learning at all, Duolingo absolutely wins. And, empirically, it does work for some of us, in some languages.
I think the difference is between 5 minutes a day, checking the box that you’re “learning” vs admitting that you’d be better off using an effective structured program (tutor, live language partner, etc.). I think the critique is Duolingo is treated as a substitute when it’s a complement.
Thanks for saying it that clearly, this is exactly what I think of it too. I try to explain that sometime to people (irl), but despite my own achievements regarding language learning that should back my advises the truth is too hard to handle for most.