why do ppl say dragonball z is overrated?

Because they don't understand what the series meant to Japanese animation. If you just watched the series for the first time now you'd say "Wow this plot is stupid and the animation isn't great." For those of us who grew up with it though, and for those with common sense, we see it as the series that launched Anime into the US. It also inspired hundreds of modern writers and animators.

I 100% agree with Lyar.

Dragonball Z is one of the greatest anime classics ever, it's a legend for what it did for anime.

People should respect it, Dragonball Z will never be overrated to me if anything with the generation NOW it's underrated.

Because there isn't much to it. It is over-rated. But that doesn't mean its bad. Just "not as good as everyone says." The series was great with character development, and things like that, but seriously lacked an overall plot. And yes, along with Gundam Wing, Dragonball Z helped launch anime dubbing as a serious and profitable effort.

It's good but not that good. The story is the same with every enemy. Yu-Yu hakusho is much better. Not every good action anime has to be over 9000 episodes.