How much has this duolingo course helped you after finishing tree?
I'm currently working on the korean tree and i don't expect to become 100% fluent in korean because of it. But i do wonder however how much it has helped other people with understanding korean after finishing the tree? For example: can you understand most of the lyrics of a k pop song now or can you read a simple news article?
Hard to say because I haven't used just Duolingo. I do usually understand what the songs are about even if I don't understand 100% everything. News for me still depend on the news. ^^' Duo mostly helps to learn basic grammar and vocab and yes, for example quotation might be something useful when it comes to understanding basic news. But to do so I do admit that one would need more sources than Duo. For example 1000 most used Korean words is something worth looking into. There is a vocab set like that on Memrise if you use the app, or you can also find the list here https://www.topikguide.com/6000-most-common-korean-words-1/. I heard that knowing 1000 most used words of a language can help one to understand even 70% of all the basic texts they read, and 2000 words 80%.
If one properly learns everything that Duo has to offer I believe that they should very well be able to understand grammar patterns on the kind of level that they can take unknown patterns apart to find out what they mean, know what to look for to find out what they need and just have somekind of a basic instict about what sounds about right and what does not.
It's good for supplemental learning not as the sole source. So I'd say after completing the tree I have improved upon the Korean I already knew not really learned more (other than a few words). In terms of understanding kpop lyrics or reading news article I'd say a hard NO. You simply don't learn enough from duolingo to be able to do that and you don't really know what you are learning. It's more like an applied phrase book than an actual explanatory learning tool. You don't learn why you are using certain grammar points, you just copy them so then applying your knowledge outside of duolingo becomes a challenge because you don't actually know the rules of the language.