I looked up on a whim what was going on with the Candle Power Forums now. Somehow it's still active, but there's a separate forum - Budget Light Forum - that acts as a competitor and seems to be full of people who deride it for being "run by a woman" or "a ghost town". The latter may have been true at the time (2021) but it seems pretty well used at the time - for practical purposes (at least as practical as the flashlight hobby is). Candle Power still has more going on than r/flashlights, which is mostly people showing off how bright their flashlight is when the power goes out (and additionally showing off how well their personal generator functions to bring the lights back on when there's a snowstorm).
I'm not going to look through anything else there, as I'm unlikely to find anything beyond what was discussed in the episode without really looking for it.