I can wrap my head around zooming in - conceptually you run any life simulation you want, i.e. a base level game of life, and then recursively decompose each cell into the 2²² cells of a OTCA metapixel.

Zooming out I find much harder to make sense of. What does it look like if you zoom out infinitely often? Is there some limit? If you take an empty universe with all cells dead there seems to be nothing at first, but at closer inspection there is of course still a lot of stuff going on in all the dead metapixels making up the empty universe. After zooming in a couple of times it would be hard to tell that zooming out a bit would leave you with an empty universe. And it would not have to be an empty universe, it could be anything.