Nordic countries did this. Birthrates have been declining regardless. Even Gulf Arab countries which are an even more enviable welfare state, and have considerable religious-cultural emphasis on childraising, too, have seen declining birthrates.
Do you aware how expensive Nordic countries are to live in and have social life even counting all the free stuff?
And gulf arab countries are basically even worse in this regard.
Very high educated well earning women can offload their duties to others even the getting pregnant part these days. Educated women also tend to have a higher desire for large families, I know families with large amounts of engineers/lawyers/doctors where almost all get more than 2 children.