Hytale is different in terms of gameplay (or so their trailers show). It is more focused on multiplayer and adventure, minecraft although it has multiplayer is more of creativity and something of multiplayer.
Regarding the question, Minecraft has that something that always makes us play it again, I do not think it dies or leaves it aside because the community is enormously large. It has that unique touch that other games fail to give the player.
Anyway, hopefully if Hytale is not free, at least be cheap.