D&D has been growing at an unprecedented rate for years. It's bonkers to expect that growth to continue indefinitely. Anyone saddled with being in charge of D&D is going to see it slow and cool under their watch. The bubble will burst and the fad will end. That doesn't mean it is going to die, unless execs try and kill it by wringing every laast dollar out of it in the short term (as they are wont to do).
That said, if I were put in charge and expected to keep D&D growing, I would double down on accessibility (including new starter sets) and Beyond/VTT. And I would pretty much ignore my own (50 years+) cohort, leaning into properties and settings kids actually care about rather than trying to bring back my favorite setting that wasn't actually particularly successful when it came out 30 years ago.