Gizmodo recently did a story on Stranger Things pinball during their coverage of CES, and when they did their recap story at the end of the exhibition, they included it in their "Best of CES" list!
A mainstream tech blog (which is mostly staffed by and aimed primarily at Millennials) covering a pinball machine and touting the benefits of the "analog" experience it provides is definitely a good sign that the pinball revival isn't merely wishful thinking on our part and might have some real "teeth".
However, I am almost certain that the Stranger Things theme played no small part in getting their attention in the first place, and that the same pin with a dinosaur Rock band or 80s movie theme would have hardly been looked at twice (despite the great tech). This can serve as "Exhibit A" evidence that themes need to be modern and relevant in order to capture the imaginations of younger non-pinheads; "Boomer"-centric themes aren't going to cut it at this point, especially given that slagging that entire generation (and its cultural touchstones) at every opportunity seems to have become the trendy thing to do these days.