I will offer a counterargument: there's a disconnect between the text of Snyder's films and what people took from it because so much of the critical discourse around movies today has been homogenized, notably through things like review aggregators, but also in the endless youtube hot take industrial complex.
The consensus around Zack Snyder and his movies is that he's some idiot jock who doesn't get the material he's adapting and who just wants to do big crazy visual spectacle. All of his movies are then looked at through this prism, and it becomes a self-fulfilling prophecy that people are all too eager to peddle because well, that's the consensus.
The problem is that, in order to make this work, you have to have a viewing of the text so selective that all subtext, and key parts of the text itself, are left completely ignored. It leads to completely sterile platitudes like "this isn't my Superman", "Superman doesn't smile", "okay, Superman does smile, but he isn't shouting directions at people", and that discourages debate in a way that is helpful to no one.
So your answer to "the audience didn't connect with that version of Superman for some reason" is "YouTubers have poisoned an entire audience against Zack Snyder"? That seems to be deflecting at best and ignoring a large swatch of viewers who aren't on the younger side of things.
For example, take the CinemaScore. Now, CinemaScore doesn't mean anything in the grand scheme of things, but audiences leaving the film gave it a B. Most films score rather high on CinemaScore's ratings, but usually they begin to fall when there's a divide between what the audience expected when they entered the theater and what they actually got.
Man of Steel got an A-, meaning they disliked it two grades more. Superman Returns got a B+, as an example, showing that audiences were more satisfied with that film than Batman v Superman.
Burton's Batman: A
Batman Returns: B
Batman Forever: A-
Batman & Robin: C+
Catwoman: B
Green Lantern: B
Every Nolan Film: A
So, there was some level dissatisfaction with the average moviegoer. You could talk about a certain amount of drift from YouTube critics, but to that degree?
Let's add the Snyder films for good measure.
Watchmen: B
Sucker Punch: B-
300: A-
Dawn of the Dead: B
Legend of the Guardians: A-
In contrast, Man of Steel was enjoyed more than most of his films. BvS represents a large drop, putting it in line with Sucker Punch, one of Snyder's more personal and creative-driven films. It's not Snyder, it's something with BvS (and Sucker Punch) that isn't resonating.
I'd argue that people were willing to overlook some of the issues they may have had with Superman's portrayal in Man of Steel, given the excellent fights, great casting, and top-notch cinematography. It's when perceived issues weren't addressed a second time that they turned.
If you look at
Rotten Tomatoes audience ratings (63% liked, 3.5/5), they show that dip from Man of Steel (75% liked, 3.9/5). Green Lantern sits as a bottom-line (45% liked, 3.1/5), and Batman Begins (94% liked, 3.9/5) offers a decent top-line, thought Dark Knight is higher. Same over at IMDB, where you can see BvS (6.6/10), Man of Steel (7.1/10), Green Lantern (5.6/10), and Batman Begins (8.3/10). Metacritic user scores actually lineup pretty well with the IMDB numbers: BvS (7.0), Man of Steel (7.5), Green Lantern (5.8), and Batman Begins (8.6). And none of this account for Wonder Woman.
So, there's a dip. Why? Why did the audience have a large problem with BvS compared to Man of Steel or other films? DC films make money and get high ratings when they're good. Snyder has had successes in the past in telling stories in film. It's just there's a disconnect with this one and blaming it on poisoning the well doesn't seem to engage with the problem.
Veelk offers that the scenes shot are not portraying the emotion that Snyder and Terrio wanted to get across. That's why he offered the Framing Megan Fox video, which points out that folks see Fox as purely sexualized in the first Transformers, even though the text gives her a great degree of depth and agency. His guess is that Snyder wanted to say one thing, this being the text that folks like Bleepey point out, but the scenes as shot give much of the audience
a different feeling. Which is why you have folks grasping for any reason that it didn't resonate, but not necessarily being able to pinpoint the exact reason.