That's really sad news ๐. Duolingo started as a great platform to learn languages for free but has more recently focused on profits and a recent IPO. The course content has suffered considerably (speaking from the Spanish course point of view).
I'm actually surprised that they still had volunteers and don't understand the decision to stop the Welsh course being edited. It's not like they make a custom course per language, it's all generic and then the content is different. Anyway, fuck them.
I wonder how hard it would be for the Welsh assembly to recreate a Welsh version of the app on their own? They have talented Devs that could do this and volunteers that already curate the language courses. Cut Duolingo out of the equation.