Not disagreeing completely but that's like saying 90s or early 2000s music won't do well in today's music environment.
Many have called Naruto and One Piece their inspirations. Some stated how they looked up and tried to match the "cool" nature of Bleach.
It's just important to keep in mind that the popular things today were inspired by those past things. Meaning without those influences, the things you like today or are the norm today in the industry might not have existed. It would've been a different era in the manga industry if those popular titles didn't exist.
Here's another question.
If One Piece, Naruto, Bleach, Death Note didn't exist from the previous generation, how do you think would it have affected the popularity of manga around the world?