It just looks to me like he had all of the parts that overhung the sidewalks and street removed, in compliance with the Health Dep'ts order. He saw his opportunaity and he took it, being understandably frustrated with the city's failure to maintain the tree properly.
As bad as it looks, I am looking out my front door at an only slightly smaller tree across the street that the County had pruned, pretty much to the same extent, to prevent encroachment on power lines and danger to my neighbor's house. I didn't think it would live, but it has sprouted a few new limbs and seems to be doing okay, though it's ugly as sin.
I'm not sure which is worse - the way they mutilated that tree, or the fact that many of my neighbors have had the very large old trees in front of their houses totally removed by the County, claiming that they posed a danger to their homes. The result is that Main Street, which used to be tree-lined, has very few trees left. I can't say I like the way it looks.
I know that having to rely on the County to deal with streetside trees has been a major annoyance to many of my neighbors, who have had to wait for a LONG time before the County got around to doing anything about the trees. In fact, I'm sure that's why most of them chose to simply have their trees removed - because the County couldn't be counted on to maintain them properly.
In any event though we all know that the trees (the few remaining) are on the public easement and thus we cannot removed them ourselves.
LOL. That tree was not "pruned". It was delimbed to kill it in a way that is done before a tree is to be cut down.