For all the tens of millions Mayor Bill de Blasio keeps throwing at his East River ferry service, it’s no progressive triumph.

Indeed, its ridership tilts upscale, as The Post reported this week. Just 36% of riders are nonwhite, and only 35% make less than $75,000 per year. City Councilman Donovan Richards of Far Rockaway told The Post it’s a “reinforcement to communities of color that they don’t matter.”

It’s not even delivering the promised reduction in bus and subway commuters. In fact, according to the NYC Ferry’s own report, only 35% of riders use the boats for more than four trips a week.

All a great embarrassment to Mr. “Tale of Two New Yorks.” Perhaps that’s why, in an apparent violation of the open-records law, City Hall sat on the info for months after The Post started requesting it back in April — then released it first to another newspaper.

His pet project may be a failure, but at least he didn’t have to read it here first. What a giant.