Lots of us on here can remember back to the days before local-paper adverts, for WG's, first appeared.
By "on-line platforms", do you mean AW?
AW is no more risky than the local-paper ads but is lots less risky than "street-work".
Risk is mainly set by where the WG operates. Rural home-counties are more or less risk free.
Many girls in such areas work from their homes, with no real security. In the old days they always had a "maid"
In about 2010 one old hand told me that AW had "changed her life". More well heeled clients and less expenses took her from "making a living" into clearing a lifetimes accumulated debt and then owning a smart flat in a South-coast resort.
Women in their 50's, that could not get safe work in a parlour any longer, now had a way to market themselves.