Just curious on what people's take on this is.

In the topic of games, there aren't many mechanics that haven't at least originated from a similar mechanic found in another game, or that don't resemble mechanics from other games in some way. Especially with games in the same genre (how many RPGs have the "strength", "intelligence", and "agility" as "stats"?)

So my question is, would you consider it unoriginal/bad/unethical/(any other negative word) if a show copied systems/pieces of setting/lore in other shows? For example, if you saw an anime on TV one day that had extremely muscular dudes flying around punching each other through mountains, occasionally stopping mid-air and yelling for 2 minutes straight, would you say "That's a Dragon Ball Z ripoff. I'm out of here!" and switch the channel? Is there a certain amount of similarity that you can take before your threshold of tolerance is broken, and you curse at the creators in your mind and call them unoriginal punks?

I'm also interested in what you think the general public would think about a situation like this. Using the DBZ example above, do you think certain people who've seen DBZ would enjoy the "references" made in the anime, while those who haven't seen it would not notice at all?

There's a few different situations covered here:
Copyright infringement - If I significantly copied the DBZ story/setting but changed the names and had it reanimated, that would be prosecutable under existing copyright laws.
Paying homage - by making a subtle reference that my scene is similar to a DBZ scene, I'm paying respect to my influences and giving the fans an inside joke to enjoy.
Reusing tropes - DBZ contains a lot of tropes. These are like clichés and memes, in that as individual elements, they're meant to be reused by authors and quickly recognised/understood by audiences.
Derivative tripe - when I don't copy someone blatantly enough for it to be obvious copyright infringement, but I also don't pay homage to them or admit them as an influence, and I don't bring anything new to the table; I only recycle old unoriginal clichés. This is the staff you switch the channel from.

Here's another interesting thought experiement: Suppose you have a million people who are going to be music composers. Assume that they're all reasonably interested in music and have some base line skill level. Each music composer is raised in a life without ever hearing music, so they live in a musical vacuume. Now, you give each one two dozen musical intruments and you instruct them to play with the instruments and to come up with some nice noises. They have five years to complete the project. So, in essense, you've got a million people who are uninfluenced by music they've heard, trying to create truly original music.

Of the million composed songs, will any be very similar? I hypothesize the answer would be "yes". First, you've got the consistency of human taste for what sounds good and what doesn't. Second, you've probably got a birthday paradox going on in terms of musical note selection and patterns.

So, how does this relate to the original post? Nobody creates from a true vacuume, so you're always going to be influenced by other creative works. In a sense, we bootstrap ourselves creatively. The creative products are also susceptible to the natural selection effects of the mass market forces. The creative works which do well are those which have appeal to a large group of people. When creative people create, they look at the creative ideas which worked rather than the ideas which failed. Then, they reuse the working ideas (in this case, game mechanics & theme) and add their own tweaks and changes to create a "new" work. For example, the AD&D system originated as a table top pen and paper game. The mechanics of this game system have been replicated many, many times with some tweaks and changes (too many games to list). Thus, you get a whole genre

Of the million composed songs, will any be very similar? I hypothesize the answer would be "yes".

There was an ad running months back that promised a new TV show about Peter Pan, from the perspective of Wendy, which reeked of everything that got left over from Twilight. So it fit Peter Pan squarely into the genre that Stephanie Meyer had built up. Wendy was just Bella, and again with the need for this perfect fantasy ageless boy in the girl's life. I don't think that show ever materialized...

Some ideas get worn and played out. Some combinations of ideas... are just terrible.