I'm not sure about the OCP credential bit. I've see posts on this very forum where folks say the actual exam question papers are available for a price. I've seen people ask for sample "dumps" here. Then I've seen the most inane questions about how to configure a listener come from OCPs. Given all this, it is not surprising that an OCP credential by itself doesn't mean much these days.

Well, I'm an OCP(7.3,8,8i) myself. But I used to take the tests to force myself to learn new features right away. It didn't make job hunting any easier. Not that I expected it to either.

To me - concepts, analytical and communication skills are primary. If a person can draw and explain the architecture of an Oracle database on a white board without having to think twice, s/he is 50% through. Sounds simple enough - but ask a "senior" DBA this and 8 times out of 10 they will goof. Who cares if a person can't answer nitty gritty commands/syntax in RAC or Data guard. It doesn't take a decent DBA long to figure the stuff out.