Nope. Gintama started long before this season.
Hint 3: The show is set in the past.
was manyuu, your hint is invalid.
You watch the show, and not know it's not set in the past, it's just like gintama, it's not set in anything.
In this current era, breasts mean everything. If you have breasts, you are guaranteed wealth and popularity.
It's own era. Your hint is invalid.