Fortnite is like the opposite of Morbius in that it's a good game yet everyone trashes it because everyone else on the internet also does too.
The crossovers, the gameplay and the fortnite funny family guy moments are actually pretty good, but because it's a free game available for PC and Mobile (more children can play) and many children content creators played it it just kept getting more popular, drawing in lots of kids.
Young kids are especially prone to raging hard on videogames, and hate for the fortnite players somehow just became a hatred for fortnite in general.