I live in France too. Your comments are just wishful thinking. Christine and the Queens is in no way considered a has-been in France, he is very much considered in France, not always understood but he is a national treasure and people are quite aware of his international impact (as far as a French pop artist can be). Sales are not relevant, the artists you refer to, like Brigitte Fontaine, do not sell well either, far below even.
You project on him a lot of negativity and you clearly don't like him but do not try to spread fake news about him, when that's just your opinion, not reality.