After failing to renew its fanbase, it's like they gave up on it. Could Ultraman ever be put to a permanent retirement?
I think there's too much demand for Ultraman stuff, even now. This is just a thing that happens with Ultraman, from time to time-- the show goes into a period where not a lot of original material is being made, even though older stuff is being rerun pretty steadily. The first period like this ended when Tiga went on the air, I believe. The current period will probably end whenever Tsuburaya manages to get the budget and the timeslot to support a new original TV series. In the meantime, they'll do stuff like Ultra Q Neo and Retsuden that's weird but not uninteresting.
And maybe they're right. Why did Toei waste it? Because they are interested in money, not telling a good story.
I dunno that I buy this. Toei hires living, breathing human beings to create these shows, and I don't think any creator wants to put their name on a shitty product. I don't think any Sentai series is bad on purpose. I think instead, people get overwhelmed trying to fit in all the things that they have to do, and end up without the time or energy to do anything really special with the story.
Like, I ride Go-onger pretty hard, because it's one of the few recent shows where I can't imagine it being good without literally just imagining a different show that already exists. That said, I don't think Go-onger turned out like that on purpose, or that Toei viewed it the way I do. I think a bunch of creators got together and got nostalgic about Carranger after the car theme was handed down, and decided to try and do a modern show that could entertain modern kids in the same way.
Den-O was huge at the time, so it was reasonable to think that the time was ripe for kids to really get into comedy Sentai. But between Hikasa's burnout and the usual problems of putting together a weekly TV show, they just never got around to making anything really inspired, or putting their own stamp on the material. They ended up making an inferior imitation of Carranger and Den-O both, which I'm sure nobody set out to do.
I loved the flashback episodes in Gokaiger. I think a series made out of that setting is something I would have enjoyed so much. Though, given the formula Sentai goes for, I'm not sure that's sustainable over a year long series.
Sentai has pretty much already done this. Gokaiger's approach to setting was lifted wholesale from Carranger, right down to the characters reading space newspapers about their own exploits. The only real difference is that Gokaiger treats it seriously, while Carranger used its setting to develop a lot of running gags involving various alien visitors to Earth. So where the Carrangers have a goofy fake Space Sheriff who wanders in and out of their storyline, the Gokaigers have significant interactions with the actual Space Sheriff Gavan. And where the Carrangers had to put up with weirdos like White Racer and VRV Master, the Gokaigers get their power-ups from actual Sentai heroes who can be taken seriously. You also get the Zangyack as an acutal all-consuming evil from space, where the Carrangers get a silly parody of that in Lord Exhaust.
It does annoy me when people make out the Gokaigers had NO character growth or were "just like the Goseigers."
Well, they are just like the Goseigers in that all but Red are literally characters who have already been in other shows. That's a reasonable thing to do in the context of an anniversary season, but it will invite comparison between that cast and prior casts. Gokaiger has it a bit worse, though, because the performers get painfully out-acted by just about every single returning guest stars. I think only the Gekiranger and Gaoranger eps didn't make the main five Gokaigers actively look bad in some regard, just on an acting level. I mean, the scenes between Yellow Lion and Joe? Kazuhiko Nishimura absolutely came off like he gave more of a **** about Barizorg than Yuki Yamada did.