It's not a diss, it was an ok movie. Most people consider it less great than 4 and 5, partially because they redid the big scene in 4.

It did feel derivative, but then they just did it again with one of the sequels because they could, except this time it's a death planet instead of star/moon. The Empire or whatever they called it had been reduced to a parody / comic relief.

And somehow the death planet also has a self-destruct. Well, parody is a good way to put it, the sequels are about as Star Wars as Spaceballs is.