Yea, um. About that. It's "modern" all right. If 1986 is "modern".
When you look at what guys like Matt Garrison, Hadrien Feraud, Janek, Damian Erskine can do, it appears to be this cutting edge break through new fangled technique thing. Now, all those guys are monsters and have more than their fair share of unique ridiculoso happening, but the idea of how they do that right hand technique has been around for a long long loooong time.
This video is from the 80's and Abraham Laboriel shows how he used the same three and four finger technique way back then. In the olden days, you know, before the internet. He says it comes from classical and flamenco guitar technique, so it may very well be hundreds of years old then.
Every thing old is new again as the saying goes.