Remembering technical details in long run

No, they remember it bcoz they have done things hands on multiple times and what they remember are base concepts(basics). Things change, technology change but all those are upgrade of what already exists out there. It's all about fundamentals and how you breakdown a big problem into small manageable chunks using first principles to deep down and solve it

Just remember the basic patterns and good practices. Usually the revision automatically happens due to multiple demo, presentations, or even knowledge transfer sessions.