What I find consistently ironic is that the people who hate Braga the most tend to give him far more credit than he's actually entitled to, and at the expense of the collaborators he always works with. They elevate him into this all-powerful solo auteur who deserves sole credit/blame for every show he works on, when in reality he's simply a workmanlike producer who has always been part of a team and has built his career mainly on being brought in to produce shows other people created.
And of course, part and parcel of that is giving him too much credit for Star Trek, assuming he was Berman's equal partner in everything, which isn't true at all. He started out as the lowest-ranked staffer on TNG, rose through the ranks on VGR, show-ran it for two seasons, then became Berman's equal writing-producing partner for Enterprise only. For the most part, he worked for Berman, and only on selected projects -- TNG, VGR, ENT, and the first two TNG movies, with no involvement whatsoever in DS9 or the latter two TNG movies.
You'd think that the worst critics of someone would want to diminish or trivialize his achievements, but Braga's haters insist on assuming he's a far more powerful and influential auteur than he actually is, and insist on marginalizing and dismissing the achievements of Braga's many collaborators in the process. It's bizarre. They tear him down by building him up at others' expense.
As for Berman, he was the executive in charge of the whole franchise for so long that it was inevitable that he'd accumulate the blame for everything fans didn't like. The longer any producer serves, the more negativity they tend to accumulate from fandom -- look at how much Doctor Who fandom vilified John Nathan-Turner by the end of his tenure, or how much they criticize Steven Moffat today.