Hey Alex,
I can only speak to one of these questions and only from personal experience. In my time, I have not seen evidence that engineers are intentionally waiting longer to become PEs if they are able. If anything, I have seen a number of peers take the PE exam early (where allowed) so as to become a PE the day they earn enough practical experience to meet all of the required criteria for licensure.
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Christopher Seigel P.E., M.ASCE
Civil Engineer
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