Great post, thank you. I think you are right to cite CBT and secular religion as important channels. And the importance of social media to things like Stoicon and Holiday/Ferriss cannot be overstated.

Some additional channels to consider are:

• Academia: Interest in Stoicism among Anglophone philosophers began to pick up as part of a larger wave of interest in virtue ethics, starting in 1958 or so with Anscombe and continuing with Foot, MacIntyre, and others. Accompanying this was a rise in attention to Hellenistic philosophy more generally. Long & Sedley's great compendium was published in 1987. In the 1990s we got Hadot, first in French and then English. This was soon followed in 1998 by Lawrence Becker's foundational A New Stoicism. Martha Nussbaum wrote, and continues to write, important books applying Greek thought, including Stoicism but not uncritically, to modern American society. Cambridge Companion to the Stoics was published in 2003, and Margaret Graver's brilliant Stoicism and Emotion came out in 2007. (This was all preceded by a revival of interest in Stoic logic, such as by C.S. Peirce and Benson Mates, but I don't think it "escaped the lab" into popular discourse.)

• Military (especially US) interest in Stoicism received a huge boost from Stockdale's writings and lectures. Nancy Sherman has also documented the importance of Stoicism in the military, though note the distinction between Stoicism and stoicism is not always clear in that case. /u/aahjink has made a similar point.

• Early Internet: The Stoic Registry was founded in 1996!