What you are portraying as negatives (meandering detours into entirely unnecessary, but hilarious, trivia; absurdly unlikely plot scenarios [since when is anything about Snowcrash a likely scenario?]; etc.) are probably what loom as the largest selling points for fans of Stephenson's work from Cryptonomicon onward. I don't think we buy the books for the "plausability" factor.
The best textbook on modern banking and finance I've ever read.
Which, I realize, is a really damning endorsement of a novel, but I honestly found it fascinating. Once I chewed through enough (roughly half) of the first book to the point that it was engaging.
And yes, its exposition was itself an exploration of the baroque.
Some of them are. Some of them are truly pointless. Neal Stephenson apparently had a giant map of 18th century London on the wall of the room where he wrote it, and as such apparently feels compelled, on certain occasions when a character goes from one place to another, to name every street he passes on the way. That's not atmospheric or interesting, it's just filler.
Also, the books hardly take themselves seriously.