The OP has a point, but his choice of DevOps as the bugbear is clumsy. Maybe the bastardization of it by the business is what he's mad about. "Full stack" is, perhaps, a better target. It's a completely meaningless, useless phrase.
The problem is that employers demand specialists, especially for senior positions. At the same time, once they've acquired an employee, they refuse to respect specialties from that point on. Machine learning expert? Sorry, but we need a ScrumDrone over at desk 21-B. Being a software engineer means resolving the fight between your job and your career, which is probably a big part of why this industry is so political.
Employers are remarkably inconsistent in this regard. They want sharp people who can interview like real computer scientists, but get in the way of their continuing sharpness (by assigning smart people to dumb work) as soon as they're on board.
The insight that the OP has is that employers over-hire for crappy work, and he's completely right, but DevOps didn't do it.
"Full stack" is useless in the same way that "Agile" is useless. Specifically, it's useless because it was hopelessly cargo-culted and overused due to the original power of the idea.
5-10 years ago a full-stack developer was a very meaningful distinction. Today, every hacker wannabe Uber driver that went to a dev bootcamp for 3 months calls themselves a full-stack developer. "DevOps" avoids this fate only because the subject matter is slightly heavier and harder to fake.
I think a lot of people in this thread have never actually worked on a Really Big Project. Once you have two or three offshore teams, a hundred developers, associated support staff, multiple product teams, competing customer voices, multiple production environments in different locations with different support, "standards" imposed from external orgs that make no sense for the project at hand...
That's when DevOps gets really helpful and valuable. But if you haven't worked in environments like that, you have no idea what it's like.