Like if you watched the old Broly (the first one) He looked way younger, and in the DBS version he looks very old. So does that mean Goku, Vegeta, Gohan, Piccolo and Trunks minds where whipped clean?
Because of his limited appearances, fans have debated if Broly can be considered part of the larger Dragon Ball canon for years. But in a note on the Dragon Ball Super: Broly website, series creator Akira Toriyama said he worked to fit Broly into the Dragon Ball universe.
Hopefully that links confirms that Broly is canon now. The movie basically retcons Broly's origin. That's why his father looks older and different than in the DBZ Movie.
The Paragus from the old Broly movie is not canon while the Paragus from Dragon Ball Super Broly is. They are 2 separate characters and you shouldn't establish any form of relations between the two.