Erm, not all of us BDSMers want it to become more mainstream. I think it is a massively bad idea. Young people will repeat what they have seen without understanding the dynamic of ongoing consent at all.
I do get what people mean when they say once we are tied up, we are basically at the physical mercy of the Dom. Yes we are, which is why a sub should never let him or herself be tied up by someone unless they have known them intimately for a very long time. I think it was six months with my ex before I let him.
I had to know that he WOULD stop on my word, and wouldn't betray my trust, which I learned by doing less restrictive stuff with him first.
Being able to trust someone 100% feels amazing. They could in theory do anything they wanted do you. Yet they don't, because they care about you. It means you can trust that person 100% with your mind and body (in my case it feels like that anyway).
So youngsters looking at BDSM porn is dreadful. None of what I have described is.conveyed. None of the trust needed. BDSM passing into the mainstream is bloody corrosive and gives abusers a charter for violence. Unless all the nuance and safety precautions taken in BDSM is also conveyed, then things will go terribly wrong.