I love doing multiple tech things. Development, Ops and security. Why can't people see this as tech experience and not individual subdomain experience. Why can't people switch jobs easily over Dev, Sec and Ops?
Smh.

Dev(Sec)Ops may just be a buzz word: Software always had to be developed, secure and deployable. The question is if specialists of each field are required (everyone should know the basics of the other ones of course) or all-rounders.
The difficulties might depends how people start in the field (e.g. uni and first job) so they might be focused on one and have no experience in the other fields. At my university of applied science there are two paths: "IT security and mobile/embedded systems" and " Software engineering / media informatics" while the basics are the same.

One note about the "ops" part: Classical sysadmin jobs involve little to no dev experience besides some scripts for automation.