Did Squaresoft ever say anything about the R=U theory?

[Forsaken Lover]

Just ignore that quote from Crystal. It contradicts the entire plot of the game. Here is what Ultimecia is really after.

Time compression. Time compression? It's time magic. Past, present, and future get compressed. What's going to happen to the world? Why do something like that?

Rinoa: (to Squall) ...I should tell you this before I go. I was possessed out in space. There was a sorceress inside me. Ultimecia, a sorceress from the future. She's trying to achieve time compression. She's the only one who would be able to exist in such a world.

Ultimecia: The world was on the brink of that ever-elusive 'time compression'.

Ultimecia (in her final form): Time shall compress... All existence erased.

Ultimecia is the only being, for wheatever reason, that can exist in a Time Compression world. Everything else is denied and dead.

And for all we know, Adel could have been stronger than Ultimecia.

If we want to actually give Ultimecia some "depth" we can say she is a victim of her own fear. She is the supreme being of her time but the thought of someone rising up eventually and defeating her haunts her. She seeks to remove this by making herself the only being alive. Of course, by doing so, she ensures her destruction.

It's a common plot element for characters.