- It's an anonymous source claiming 15 years of experience and technical proficiency but somehow still had to relearn basic concepts. I'm not buying it. - I would much rather do general computer science problems than have to answer questions about the framework that happens to be trendy this year or have to spend days on evaluation projects. General CS questions also allow people to transition between domains and sub…
This kind of knowledge is highly perishable if you don't use it everyday. You quickly find yourself moving from "knowing" something to "knowing how to find" an answer to "how did that go again?". It's just the nature of the business.
It doesn't mean you aren't good at or capable of picking those things back up, it just means you may need a quick refresher. Not being allowed to use references makes that artificially worse.