I love reading articles that purport to tell the public how things at Apple work. They're almost always laughably full of shit.
That implies every floor is different which matches what you are saying.
Most of the stories that have come out felt like they were the image Apple wanted to give. It started with Apple going after missing iphone that was left at a bar. We've heard those working on latest design for the next iphone were sequestered away from the rest of the company. I've always thought it was marketing spin and I'm glad we have an ex-apple employee confirming this. Back in the 'Lisa' days Apple did split and silo divisions, Apple did closely guard new iPhone designs with very few leaks happening but the rest of the mythology is more marketing.
It isn't absurd as what GP mentions was imported into Amazon by Dave Limp, a former Apple C-suite. It was a terrible culture shock for most of the ICs in my team being reorg'd reporting in to Limp, after Steve Kessel (of Kindle fame), the previous leader, went on a sabbatical.
I worked for a company that did some work for the federal government. Boring stuff. Their compliance rules essentially required that we firewall the folks with operational access to their data from the rest of the company. We included the physical offices in that to avoid certain expenses and controls companywide.