I'm skeptical of your first link which has absolutely no remarks about data collection besides a link to an aggregation tool, although I do think that the number of men who are g4p is drastically undercounted.

Studies conducted in Nordic Model countries show that the Nordic Model reduces violence, trips to the ER, and increases rates of calls to the police by extremely significant margins. (note that this source is actually anti-nordic model, look through their data to see the reality of the situation)

https://humboldt1982.files.wordpress.com/2012/12/dangerous-l...