[Red5]

70's, 80's, and 90's sentai stuck to a pretty rigid format with the story arcs, the rangers, and the villains. Each show had a villain that would betray the main villain or have a moment of redemption, there was always a ranger with something from their past they tried to keep hidden, the ranger that was overly care-free and it annoyed the "by the books" ranger; that stuff gets old when you see that for about 20 straight years. The newer seasons do have more variety in the characters and have added to the tropes while getting rid of others.

No era of sentai is perfect, but each offers something that is better than the previous. Like Suzu said, it is good to see the show evolve. Go-Busters took the old school/80's and 90's approach to a season and it is considered an overall failure. I think that is all the proof that Toei needed to veto the idea of making the show like they use to two decades ago.