Super Sentai and Older Fans
As said, while Super Sentai in Japan is aimed towards a younger market, however it does get a fan base from teenagers to even adults like myself. Why do I think so? Here's a few reasons in my own humble opinion, don't be afraid to share yours:
Compared to Power Rangers (most seasons), Super Sentai even for its crazy seasons like Carranger and Go-onger do feature a more realistic view to a modest extent. Yes, injures are more likely to happen if some giant monster swatted you like a fly except for Kakeru Shishi.
In Super Sentai, there are various tease scenes where some of them involve really hot girls. Many of the girls in Super Sentai are really that hot nowadays compared to Power Rangers. Not only hot, they perform bad-ass action even for the physically weaker ones.
Sentai so far has some average to really good acting even for some beginners. In fact, I find Burai's evil laugh better than Tommy's. As of recent, I really find Shinkenger's acting better than Power Rangers Samurai which I felt was also wrecked maybe due to rushing the project. Sigh.
Yes, there's a degree of realism. Although it's a big bummer that Gai Yuki is dead but his death did show some realism. I have to give my thumbs up for his bad ass action prior to his death as he didn't die senselessly- he died protecting the innocent who may have needed the money to pay for a sick loved one.
Most Sentai villains scare the pants off children. Power Rangers had its own share of scary villains but Sentai villains do creep out children more. Plus, they have the personality of J-Drama antagonists as well as Chinese drama antagonists. I dared to compare Radiguet to some villains in Wu Xia series in terms of personality. These types of villains are what older fans look for.