Some books are written for their time and don't work the same when reading them after decades since that time has passed. Sure, they still give a glimpse on what kind of times those were.
Cryptonomicon was making strong distinction between the World war II era history and exciting new near future digital development at the break of the millennium. At the time the book was visionary, predicting the growth and importance of the internet and coming of the cryptocurrencies to name a few. Characters were also using a lot of latest high tech gadgets.
Twenty years later those predictions have become reality. It's nothing visionary anymore and it's hard to appreciate it until you remember when the book was written. All those gadgets feel antique by today's standards and those predictions are reality. Luckily this wasn't a dystopian book.
So instead, there is these two layers of history. It still works on those two levels, but doesn't deliver the same contrast that I would imagine it did when it was still telling things that are not everyday things.