New Updates update loaded chunks

As Minecraft is always getting updates and new things, a problem I've had and seen some others have is how the updates make a change in worlds. What I mean is when an update drops, a player has to go out and load new chunks to find it. This makes the player explore, but it also makes inconsistencies in the world, plus, in old worlds, it gets annoying and difficult to have to go farther and farther.

I think there should be an option to be able to update loaded chunks to include new features (though I think it should be optionable). I don't know if this is possible, and it might be glitchy, but this is something I would love to see in Minecraft.

I think this could be like adding the new flowers and leaf litter in forest chunks that were loaded before the update, but not completely regenerate the forest. I also think it should definately not remove player built structures, just add the new features (like changing a cave to a lush cave).