There seems to have been quite a boom in conductive paint/ink applications in recent years. From the (google) research I’ve done, I haven’t found any particular reason for “why now” .. no great materials breakthough seems to be driving the trend. Perhaps it is more a market-pull situation - more people interested in wearables and flexible tech for example.
When I saw the latest Circuit Scribe kickstarter campaign, it was a perfect opportunity to try some out.
I received a simple LiteWings kit recently, and was impressed. After making the wing kits I still have ink in the pen, so now looking for novel applications;-)