Yes. Most of them were crap, and none of them lasted more than two seasons, in contrast to Power Rangers, which lasted for 30 seasons. That is my point. Yes, obviously, any success will spawn multiple copies. I don't need that explained to me, because I'm the one who's already saying it. The part you're overlooking is that the copies are rarely as good or successful as the original.
And comparing it to phones makes no sense, because phones are consumer products, not artistic creations. If something works as a consumer product, it makes sense for similar products to work the same way. But that's not how creativity works. It's not about what you do, it's about how well you do it. The reason there are so many crappy copies of successful films and shows is that Hollywood executives never understand that, because they make the mistake of assuming that what applies to consumer products applies to fiction and art as well.