How did you establish that there is no stigma?
Firstly, no guy in his right mind and with an IQ above 50 would overlook a woman's sexual past before getting serious with her or have any doubts that OF is sex work. Secondly, read the comments under the articles about OF or the YouTube videos with OF 'models'. People know what's going on.
As far as I'm concerned, I don't believe that legalization of prostitution would magically transform wife material girls, those with the mindset for family and children, into sex workers. The idea is laughable ... those girls won't even go down the IG influencer route which is legal and carries basically no stigma.