The director of Avex Entertainment believes that if an artist like BTS was born in Japan, J-POP can conquer overseas markets

[Midnight~Circus]

That director needs a reality check.

BTS would have NEVER reached the heights they have now if they were a Japanese group due to how insular the Japanese market is. The primary goal of Japanese music labels is to maximize domestic visibility and profit but with a declining population these labels will have no choice but to shift gears and look internationally especially after witnessing K-Pop's massive global reach.

There are many music acts in Japan had/have the potential to be international household names if their labels gave them international promotion. Not to mention many Japanese idol groups have been stuck in a rut musically speaking, in my honest opinion, and are behind on music trends and sounds. 

With the huge success of BTS and K-pop as a whole, even J-pop artists have publicly acknowledged this, Japanese labels are more than likely planning to debut or push already establish domestic acts internationally in the very near future.