People think that what is currently popular is the end all of manga/anime. Being the most popular doesn't always equates being good. Take Boruto for example. . .sure it's popular but in no way is it good. If I were to pick a good action adventure shounen then it would be Eden's Zero or One Punch Man.
There's also this pattern I've noticed in Sienen lately - too many teenage based series. Sienen is supposed to be directed toward older and adult audiences. If you're going to make a story that is adult oriented then make the cast adults.