Here's a bad diagram for how I think the dimensions in Minecraft could work. Note that this isn't detailed, I just wanted to get the idea down for once and quickly.
The Host World acts like the Sun in our solar system, with all the other dimensions circling it independently of one another. Each dimension is on its own plane, allowing them to pass through eachother. When two dimensions occupy the same space, things bleed through and blend together, allowing for some odd occurrences such as sculk showing up without an Ancient City in sight, or how the End warped the Nether by seemingly hybridization the crimson forest with their own fauna. Sometimes the dimensions become too far away to interact, causing the connection to be severed between these worlds. Between these world is a space of horrors never described—except the Endermites—and serves as the realm teleporting entities travel to so they can near instantly warp wherever they want.
Is it perfect? Nope! Does it do what it sets out to? Yeah, it explains a bunch of small nothing burgers, which makes me happy! Thus is an old theory of mine that popped back into my head recently, and I just think it looks neat in concept. In execution, it's a little funky, near definitely unintended, and doesn't really solve anything lol. Imagining the dimensions as these massive cosmic events in the making, where one day all of them will align and the gates will open and let lose all dimensions is just a really cool idea tbh, even if the likelihood is slim. Thankfully, my hand canons trump canon because I said so.
