As someone who has been doing DevOps for 20 years, since long before it was called "DevOps"...
First, DevOps has degenerated into a meaningless buzzword to rival "Agile", despite the good ideas and good intentions. Every day, I have recruiters looking for "DevOps". A couple of years ago, they'd never heard the word.
Second, DevOps is actually getting strongly biased toward Ops, often to the exclusion of Dev. In the eyes of recruiters and much of the industry, it's become synonymous with "Chef/Puppet/Ansible automation", a set of automation tools. That's stupid.
Third, and this is what matters to me... DevOps is (or was meant to be/should be) more about organizational structure than skills. As the author points out here, specialization is good and necessary. But specialization comes with bureaucratic compartmentalization that makes working across org boundaries very difficult. When you have to climb four or five (or more) layers up the org chart to find common management for both the dev and ops sides of a project, then the dev team has no authority over and very little way to communicate with ops, and vice versa. For most large organizations, the dev/ops separation is necessary - developers get locked out of production systems to keep them from legal exposure to customer data (HIPAA, PII, etc), and to keep them from accidentally or intentionally altering production in a way that it might break.
Read Gene Kim's excellent quasi-fiction book, The Phoenix Project. It covers a lot of the issues of DevOps as fixing communication patterns in large organizations. You'll see how little of it is about tooling or "full-stack", and how much is about clearing bureaucratic obstacles to effective communication.