Hardcore bands "evolving" into other genres

I believe all artists should take multiple risks throughout their careers. Art should challenge repetitive narratives and encourage critical thinking beyond genre. There's nothing wrong with making a living off of music. 

However, I've noticed that some bands who started off in underground hardcore and undergo a sonic identity shift shortly after gaining widespread recognition describe it as an "evolution," possibly implying that hardcore is one-dimensional, a phase, and not much more than a stepping stone toward mainstream opportunities. They promise it was creative dissatisfaction, not marketing.

Is genre-switching the only way to take risks in hardcore? Or is it a rite of passage after ticket sales hit an inevitable ceiling? Is that ceiling truly inevitable? And is success solely defined by commercial terms?