I’m familiar with edging, but I’m not sure I see the joke. That might be because “edge” feels somewhat semantically separate to “edging” in my mind. As a clearer example of what I mean, if the word “edgy” came up, I would be way more likely to think of it as describing someone or something that tries too hard to be dark and provocative. I’d be very confused if someone used “edgy” as an adjectivified form of “edging”.

Besides that though, I’m sure that edging was a thing 15 years ago; the Wikipedia article for “edging(sexual practice)” dates back to 2006, for one. Part of why I didn’t get the joke is because I can’t think of any logical link between edging and 15 years ago, so I think I concluded that the meme wasn’t about the sex thing.

Is there still something I’m missing, or am I just being supremely autistic about this?