J-Pop wasn't mainstream enough like K-Pop. There's some famous groups like Morning Musume or AKB48 some people can recognize very easily. As you say, they new bands like Babymetal or LadyBaby (Kawaii metal bands) who became popular for crossovers like Super Mario Maker. And a lot of other pop bands became very popular for their Anisongs from ClariS to Momoiro Clover Z.
K-Pop was popular back in the late '00s, games like Audition and the Dorama mainstreams made these songs popular, after that, Gangnam Style made Korean music a main focus, and now, many of the japanese store are now selling Pepero and Poporo merchadising.
The Japanese media has to promote their own music, like in the early '00s, when you can find people who talk about L'Arc en Ciel, Orange Range, Rip Slyme, Nobodyknows+, HOME MADE KAZOKU, Sukima Switch, Kumi Koda or Asian Kung-Fu Generation because of their songs appearing as an opening/ending song for a certain mainstream anime.
Once you're aware of your own art, you can train yourself to identify and replicate the "good" ones...
And hands off the bad ones.