Game Characters have more meaning and influence then what you say. I don't remember you being plot line creator :/
Remember, anything stated in a game, such as a prophecy, or foreshadowing WILL come true, unless the person is stated to be a lying/liar/cheater/scammer.
And again, that one line is countered by a large deal of evidence.
How is it irrelevant when Squaresoft copies motifs and ideas from all of its games, and just reworks them?
Because this is Chrono Trigger. If you're going to argue what occurs, you support it with evidence in the game itself. Games made by the same people, unless directly referenced as being part of the plot of Chrono Trigger and Chrono Cross, are irrelevant.
Because Fiona's forest isn't required, it's not canon. Probably just like getting Magus isn't exactly canon, otherwise he'd be in the group picture, and not in the antagonist scenes.
And if you do not visit Fiona's Forest and see that cutscene you will see a different, slightly smaller cutscene during the main ending that states the same thing only more succintly, as I already pointed out. Pay attention, please.
As for Magus: spoiler reasons. Furthermore, Magus surviving IS canon, as seen in Lucca's letter in Chrono Cross. She mentions Janus, and why would she do that if Magus did not survive? Hell, if he wasn't supposed to survive, why give the player the chance to recruit him? The sheer fact that he is recruitable suggests that is more likely to be canon than not.
Furthermore, if the planet was dying, and it traversed all of time and space, then it would be dead the moment Lavos did his attack. And since Crono and co can go to the End of Time and then still go back to the past, the planet probably lived up to the end of time -.- Otherwise then we'd have issues.
Why is this required? The Gates are not sustained by the Planet, merely created by the Planet. Furthermore, Gaspar says that the player can always use a Gate to access the End of Time once they have been through it, suggesting that the End of Time is disconnected from the normal flow of time rather than truly being the End of all Time, which is ridiculous because then nothing could happen in the End of Time...everything would either happen at once or be frozen.
Secondly, Mother Brain isn't "corrupt". Mother Brain is stated by the game to have gone rouge, as in it defied it's original programmed orders, and does what it wants. This might be due to its high grade AI.
She is noted as the Mother Brain of the R-Y Series Factory. This suggests she is, at most, an A.I. designed to oversee the construction and programming of the robots produced there. There is no reason to suspect something was lying wait in her programming that would cause her to be so bloodthirsty towards organic life; safeguards would be in place to prevent that kind of thing. I know that if I were to program that kind of complex A.I. I'd be damned sure to include safeguards, a sense of morality, and other programming to ensure she wouldn't go crazy. The events of the Day of Lavos corrupted her programming, pure and simple.
Moreover, we even see the seedling grow in the future. If the people had no future, then the seedling wouldn't grow. Heck, the people themselves said that they'd try and bring about a new future. The only problem was that Mother Brain wanted to create a new world from the ruins.
I'll give you something of this, but that one seedling would not support a population. Even taking into account the gameplay necessary reduction in numbers, human population is not sustainable by 2300 A.D. They're barely hanging on as it is with the Enetron.
And don't forget that CC stressed the fact that changing the future wasn't necessarily the grand scheme of things as they should have been done. The people in the future would have continued to live and live on, but it was Crono's interference that stopped them from ever being born, just because they didn't want Lavos to ever awaken.
Are you talking about Lucca's fear of reprisal from the futures they sent to the DBT? Once the future was changed and Lavos did not destroy the world, those people never existed. They wouldn't have a chance to do anything. If there was a version of them in the new future, they were much happier, safer, and lived a far better life than they would in the ruined 2300 A.D., presuming they could survive much further beyond then.
And you also didn't answer why Lavos would leave his spawn on a dead planet, if they need energy to mature and leave -.-
Yes I did. I said the Planet was still dying by 2300 A.D. Lavos himself did not finish off the Planet: the Lavos Spawn did. Since Death Peak is the likely point of eruption by Lavos, it is the best place for the Spawn to inhabit so they can suck the remaining energy. Once they finish and blast off into space, the Planet would be truly dead.