Dire Bare
Legend
While, yes, D&D was growing significantly before Stranger Things and also Critical Role . . . YES, Stranger Things is a great advertisement for the game. Being nerdy isn't feared and avoided anymore, like it was in the 80s and a lot of folks of all ages IDENTIFY with Mike, Dustin, Lucas, and Will. I know a lot of my middle-school students, since Stranger Things debuted in 2016, correlate Stranger Things with D&D.D&D 5E was already growing by double digits before Stranger Things or COVID. Besides, is ST really a great advertisement? Nerdy kids playing in their parent's basement is just reinforcing the trope that it's not for everyone. A lot of things contributed to 5E's ongoing success, and I don't expect a second boom. I just get tired of this repeated canard that the playtests and resulting rules, presentation, pace of supplements, basically everything WotC did had nothing to do with it.
It's likely D&D would be super big today without the help of Stranger Things . . . but it did help and was (still is) a good advertisement for the game.