Two solutions-
1. Re-issue the old stuff. Just some sort of fancy "collector set" with reprinted big ol' Darlene Maps and charge a ton of money. It won't attract the new gamers, but will keep the olds happy, and would "celebrate" the setting. Of course, it will also result in the death of it ... given the lack of new gamers playing it, but still!
2. Make something good.
I want to emphasize (2). I mean.... what you were just saying could have been said about 5e. At the time, the D&D fanbase was passionate, and intensely fractured. Yet 5e worked, because it was good.
It's the same with anything. You can never please everyone. But when you make something that's good, that tends to work out.