And I would add my own anecdote. The state decided to build a new office building by "selling" the land to a developer, who built the new building, that the state now leases. Also, the state passed a special law exempting this site from city zoning restrictions. The developer took out the parking lot and put up a multi level garage, for which they charge the office workers an annual fee. So the workers fanned out and park their cars along the streets in the surrounding neighborhoods, leading to congested streets and more traffic. The residents petitioned for "no parking" and "2 hour parking" signs along the streets in front of their houses. So now there's a 2-hour parking sign in front of my house, which I didn't ask for.
My point is that an innocent measure to enrich a developer had a spillover effect into the entire neighborhood. And there's still a bunch of undeveloped land on the lot, which the developer will be free to do with whatever they want. This kind of stuff fuels NIMBYism and the need for precise specifications hashed out in painful detail.
But I take your point, kids attracted to a library tend to be less likely to cause trouble. Frankly, any non-idle hands activity is better than nothing.
But that library has to go somewhere. It has to be in somebody's backyard. Just not MY backyard.
Trust is everything.