"They" are??
E6 films were never, ever restricted to, or solely for projecting. People commonly did use slide film just for projecting, but outside of what was widely assumed and taken as its one and only purpose, so very few people were aware of the many other uses for it, not for that matter did an equal number care.If people wanted prints from slides, it was in the distant past a slow, expensive and grossly unsatisfactory process, especially from kiosks. This problem only turned people off it. So entrenched populist opinion would have use believe that "slides are only for projecting!", but it has never been the case at all — certainly not among professionals in the craft or even advanced amateurs in Clubs and Groups!
What we are doing is just carrying on the way E6 films were used for print production before digital e.g. photogravure, magazine cover and page production, and particularly the way things were done in the Ilfochrome Classic print process. And printing today is far better in quality, methodology and process than it ever was in the past. I am aware of a great many photographers involved at the moment in RA-4 printing from E6 material, some coming from digital backgrounds into a sort of film renaissance.