Temporal Analysis of Meet the Robinsons

the moment Lewis found out he was the future inventor the whole universe should have paradoxed because that would mean he would know enough to not invent the hat and to put a safety in the time machine to prevent it from being stolen when he makes them in the future.

not only that but the moment Goob ruined his future it would have created a paradox as well as the hat and the time machine would no longer have been invented for him to do so.

very lazy writing here. full of continuity errors and paradoxs. can't use the old MCU excuse here that their lazy writers used because we saw in the movie that changes to the past effected that future.

what should have happened is Goob going back to help his past self become powerful and rich to get revenge on the future version of Lewis. this way if the revenge happens in the future then there would be no paradoxs from changing the past as Lewis will still become an intentor and still make the time machine for Goob to steal. the Future Goob could have patented all of Lewis' inventions in the past but let him still create them then sued him for everything he owned in the future for copyright infringment leaving him nothing. Something like that would have made a bit more sense and kept the plot holes to a minimum.