HIS, you got issues.
I use the eruv in Boro Park, don’t use in Flatbush. I heard from a talmid muvhak of a major gadol (zt”l) about BP eruv that the BP was OK, but he didn’t want to go public with it b/c he didn’t want to stir machlokes.
I haven’t gotten a definitive answer on Flatbush, but I do think it a bit childish to accuse those who do use it (or BP) of chillul shabbos. There are very learned people who take both sides.
I do know that appearances and politics also seem to creep into this – someone I know asked a local rav and he said they can use the Flatbush eruv for their baby (carry/push baby) and baby things, but nothing else. Does that make sense, logically? Not really, in my mind.