Yes, I pay attention to these things for a few reasons. First, and most plainly, if you have a bad script or bad director, A-list talent, cinematography, etc. can’t fix them. Those two pieces are, by far, the most integral parts of what make a good film, one is the story the other is the story teller, and it’s like building a house on a bad foundation. To a certain extent a good director can correct a poor screenplay since he can have some rewrites, improvisation, elaboration, editting, pacing, etc. to improve it. But a bad director can often sink everything. The former is like having Morgan Freeman read the phone book, the latter is like having Siri read the Lord of the Rings.
More specifically, the writers and directors tend to have flavors and styles that may or may not fit what I personally enjoy. I may not notice how much I love or hate a director or a writer after one or two films, but I’ve found that my favorite films often have streaks of the same director or writer appearing multiple times. Sometimes they’re not even all that great, but there’s something particular about their style that appeals to me. For example, other than Alien 3, I’ve loved or at least really enjoyed every film by Fincher, even some that haven’t been as well received. OTOH, some directors that are widely loved are hit and miss for me, Kubrik being an obvious example, where I don’t dispute his talent and vision, it just doesn’t always land right for me.
And per the OP, I’m a fan of Zack Snyder; I’ve seen all of his films but Suckerpunch (which apparently is one that a lot of people hate). Yes, he definitely has some flaws in some of his direction and pacing, but the parts that work REALLY work for me and the parts that don’t just don’t miss as much as they do for other people. But at the same time, I totally get WHY those things that hit for me don’t work as well for others and the flaws are more glaring to them. I really enjoyed the vision of 300, it’s certainly not a great story, and the characters are flat, but it seems to me he was aiming to make archetypal characters, so it worked. And, frankly, I consider Watchmen and Man of Steel to be among the greatest comic book adaptations I’ve seen. I think Watchmen was nearly pitch-perfect (and for a property many thought was impossible to do at all), and I absolutely loved the undertones of Man of Steel, exploring a lot of aspects of the character and modernizing him in a way I really related to. As a result, I was psyched to learn he was directing BvS. But again, his direction is VERY stylized and it’s like asking the mainstream audience to appreciate a more niche genre of music, some will love it, some will hate it, some just won’t get it. So I totally get how he’s divisive, and while I was hopeful for stronger positive reactions to BvS from critics, it really isn’t outside of what I was expecting–some people LOVE it, some HATE it, many somewhere in between, many left kind of confused or pointing out exactly the strengths of his I love or the sorts of flaws I expect from him.