Back in 1969, William Vickrey argued that congestion road pricing in Manhattan was a no-brainer (not his words). Ever since, economists and others have elaborated the idea thousands of times, citing its environmental, efficiency and equity aspects.
Of course, no one knew that it would take a London socialist mayor to take bring it to the world's attention (no slight to Singapore, which has been there all along, and Stockholm but London is London). And no one could have known that it would take global warming hysteria to bring it to New York (see Elizabeth Kolbert's "Dont Drive, He Said" in the May 7 New Yorker).
Good ideas eventually have their day, even if it takes time and a few oddities.