The game has the potential to cater to a lot of niches. So far, the way that some of that potential has been realized has been through the use of mods. I'm sure that we are all very familiar with TheMasterCaver's work to shape the game into something that suits his playstyle. Another well-known example is Flowerchild's Better than wolves mod, a mod that is now being maintained by dawnraider00 and saw its latest update just 2 weeks ago. The most recent case that I've become aware of has been the Order of the stone mod by the author of a recent controversial thread. Personally I've been picking and choosing mods with features that fit my style of play for many years now.
Every time I see a new thread about how Mojang is ruining Minecraft, how Minecraft's best days are long gone, or asking for opinions on what the best version is, all I can think about is how Minecraft is just a collection of features and how the people engaging in those discussions will always argue in favor of the version (or moment in time) in which the game's features most closely aligned with their own preferences. With this in mind I honestly believe that giving players the ability to taylor their own experiences through the creation or use of mods and only releasing updates to improve the game's performance would be the best way to keep the majority of users happy.
The divisions between players over very specific features have been a thing since the early days of Minecraft. We have PVPers, redstoners, builders, miners, explorers, golden-age minecrafters, minigame-players, and so on and so forth. Maybe if all of these groups were left to form communities around mods catering to their respective niches and were no longer competing for priority in Mojang's plans for future updates the frictions between the Minecraft community as a whole would subside.
I understand that the following would come with its own set of technical challenges, but what if Mojang focused on updating performance for everyone and releasing any new gameplay-altering features as optional downloads? I know that in the past many would've be been very happy to get to pick and choose between 1.13's Dolphins, Phantoms, Turtles, Conduits, Potions of Slow Falling, Tridents, Drowned, Coral, Kelp, etc.