About 40% of the prostitutes in the UK are male. http://www.telegraph.co.uk/men/thinking-man/11169544/Are-we-...
I agree the clients are almost entirely men.
Lots of sex-worker organisations have criticised the Nordic model as something that increases the risk to sex workers. Restricting the client base to men who are willing to break the law means you've biased the client group towards men who are more likely to be violent. https://newrepublic.com/article/121981/northern-ireland-sex-...
(EDIT I don't think I downvoted you, and I think it's a shame you were downvoted. I've upvoted your other reply.)