Remember The Theory On How ScaVio Might Potentially Have Impact On Legends Arceus And How The Mainline

Remember the theory on how ScaVio might potentially have impact on Legends Arceus and how the mainline series treats time travel? Yeah, scratch that in large parts.

BECAUSE THERE IS NO TIME MACHINE IN SCARLET AND VIOLET

The mysterious pokemon described in the Scarlet Book/ Violet Book... it makes "imagination" a "reality." The weird pokemon sketched in the book, the photos of the approximated paradox pokemon - they are all built on the imagination of the expedition team Heath was in. They are a reflection of what these people expected to find in the depths of the Paldean Crater. The Legendary Pokemon on the hexagonal layers is likely building not just pokemon but items, technology out of the Tera Crystals based on what the people in its vicinity imagine.

The team envisioned to find strange creatures. Fusions of legendary pokemon of Johto's legendary dogs, or Unova's Swords of Justice. In Scarlet, the expectation seems to have been to find prehistoric pokemon - preserved in the crator without human interference. In Violet, the expectation may have been shaped by the evolution of mankind and its technology - to find traces of a civilization far more advanced than our own with pokemon evolved to fit that image.

And the artist accompanying the expedition even skeched out some of the pokemon they thought they saw or dreamed up in a haze. And THOSE SKETCHES are what would later shape the imagination of the people entering the crator. The very documentation of the Area Zero shaped how humans would continue to perceive it. And it shaped Sada's and Turo's image of what the far past or the far future might look like. An "image" that would become "reality." (Even Arven mentions how farfetched the Books descriptions sound, and how his parents seemed to have basically made this fairytale real)

I cannot yet tell why the Crystalline Legendary mentioned in those books would do that, though. Maybe it was originally a defense mechanism that was supposed to keep stuff away. Let people and pokemon imagine their fears in order to protect itself. Something that failed over time as mankind advances in technology and science, so it switched strategies to keep itself save.

Maybe the Legendary is trying to lure people/pokemon/whatever to themself - like an anglerfish dangling light in the dark ocean depths, a promise of treasure greater than your wildest dreams.

Whatever the reason is, what we know for certain is that it worked on Sada/Turo.

And the legendary pokemon began more and more to shape and create from the specific reasearch the professors conducted.

In the end, the "time machine" they built is no time machine. It is a machine that makes imagination "reality" (possibly powered by the legendary pokemon in some capacity). Maybe the machine even got constructed by the crystal pokemon bc hallelujah how do you get that much construction done in a literal Made in Abyss eldritch mystery crater without all the world knowing what you are doing. Or heck maybe the machine did somehow get constructed, but it worked more like an amplifier for the Legendary Pokemon's powers.

Either way, it explains why people would not be able to "return" from the "future/past". because the future/past as Turo/Sada imagined it does not exist.

That also explains why the AI Professor crystallizes in the final fight - they are a crystalline construction of imagination. They are Sada/Turo's ideal work partner - a copy of themselves. Something that knows exactly how the Professor thinks and acts. And when the protag squad tries to shut down the machine the illusion begins to fall apart.

It also means the Tera Crystal constructions like the doppelgangers, Miraidon/Koraidon, and all the other paradox pokemon can gain actual awareness, emotion, and sentience.

They are all the Proffesors' "Paradise" because that is how they imagined the prehistoric past/ far future to be:

Wilderness untamed and existence optimized.