Disagree completely.
It’s up there with Civil War and Infinity War, IMO.
Are we forgetting that Spiderverse, Winter Soldier, Dark Knight, Logan, Spiderman 2, Superman (Christopher Reeves), Iron Man, and Ragnarok exist then?
I mean don't get me wrong, all of those films have flaws. And I don't dislike Wonder Woman, to the contrary I quite like it as I view the flaws as
mostly campy and endearing and thus, forgivable. However, they're far greater in number and make for a weaker film than the ones I've listed and I think you can make arguments for several I didn't like Spiderman 1, Black Panther, X-Men First Class, X-Men 2, Deadpool, Joker (if you consider it a "superhero" movie), Endgame, Tim Burton's first Batman, and personally I'd have Civil War and Infinity War above WW. And if you want to go a step further and consider The Incredibles a superhero movie, which I see no reason why it shouldn't be viewed as such, that's a very clearly superior film to the first Wonder Woman.
I think the first Wonder Woman does a lot of things right. For one, Diana's fish out of water experience is charming and her chemistry with Steve Trevor works really well and that really forms the basis for the movie's strengths. The action is generally fine and the World War setting, while not wholly original in the superhero pantheon is a fun point in time to explore.I also felt the moments highlighting the era's sexism in the moments where no one takes Diana seriously because of her gender was done effectively and Diana's defiance to inequality she was unaccustomed to was endearing (though it's
almost cheapened by how narratively simple it is to have this unvetted person have the clearance to sit in on high level war meetings). And best of all really is that the movie is lighthearted when it has room to be and doesn't feel like the grimdark messes they put out with Man of Steel and Batman v. Superman, or even Justice League.
But I don't think being better than a morose bundle of DCEU crap elevates Wonder Woman to the best superhero movie of all time. I mean there isn't a superhero movie out there that doesn't rely on tropes to some degree, particularly in origin stories and few superhero movies have truly well written plots that shine even among films outside the genre. The problem is outside of some shining aspects, the movie really is a pretty by the numbers origin story (I'd say Iron Man 1 is the best superhero origin story movie to date and I'd argue that Spiderverse and Raimi's first Spiderman as better origin story experiences) that outside of finally featuring a female lead superhero doesn't really do anything remarkable with its story, action or visuals. I know that origin story tropes and familiarity in narrative structure isn't unique to the genre, but I don't feel like WW did enough to make it remarkable or even atypical in that regard. To bring up an example, Spiderverse is an origin story done well. The Spiderman origin story has been put on the big screen twice already but Spiderverse found a way to make that feel fresh. Wonder Woman, to me, didn't. Having an origin story unfold in World War wartime doesn't excise the tropes.
Being a movie set in WW1 is not an innovation just because it's a different war than Captain America: First Avenger. It's still generally the same aesthetic and while CA:FA is a weaker movie, I do think the backdrop of the war serves the film's purpose slightly better than WW.
Then you get into the characters. While the characters outside of Diana and Steve are memorable to me, the rest are memorable for mostly the wrong reasons, but the most egregious being the crew of soldiers that help Steve and Diana with the mission. They are completely superfluous to the movie. I appreciate the attempt to give these characters backstories and they were somewhat charming but they really weren't needed and contributed very little. Sameer is basically a French stereotype, The Chief, with his stereotyped name, serves little purpose outside of a little side perspective about Native American oppression, and Charlie in particular is just narrative stupidity (and another stereotype, ooh look a Scottish alcoholic, whee). They hire him to be a marksman even though everyone knows full well of his PTSD issues and the one time he has an opportunity to be useful, he can't bring himself to fire properly, then at all. Which, I get is an attempt to highlight the psychological impact of war but this has been done time and again and much more effectively. Not only does the message fail to effectively land, but it's one if not
the stupidest moment in the movie. I mean why was he brought along? Cut "the crew" out of the movie and just have it be Diana and Steve, and the movie suffers little and could've possibly even been improved with the right dialogue.
The villains are memorable only in the sense that in trying to pull a fast one on the audience with who Ares really is, the whole mission to stop him becomes somewhat incoherent in juggling Sir Patrick, Ludendorff, and Dr. Maru. And in the end the payoff is we find another tired movie trope of a villain hiding in plain sight under the cover of someone pretending to help the protagonist and in the end it just amounts to a big CGI smashfest which was exactly what the movie, tonally did not need. And what's the result of defeating Ares? Yeah lives were saved but war historically continues even after his defeat. And sure, that's as much Diana's naivete as anything but when you build up Ares as the cause of all war and you strip that away, what are you really left with? A run of the mill superhero villain that will cause widespread harm who gets defeated in a CGI smashfest that ultimately didn't have anything deep to say about anything and nothing nuanced about his motivations. If anything, Ares' plan is pretty muddied to the point of being nearly incoherent when you really sit down with it.
I don't know man, a lot of the movie works and the things that don't don't really bring it down that badly, but outside of finally having a female lead hero which wasn't really done at this level of blockbuster cinema before, the movie doesn't really do anything outstandingly well or notable. The action and effects don't set any bars, the story isn't all that compelling, the messages it aims for either don't resonate strongly or they fall flat on their faces (most of them feel hamfisted into the script for the sake of trying to have the film say something rather than to have them emerge organically from the story itself), and there aren't really any standout performances in the runtime. Maybe Chris Pine. But nothing here stands out like Phoenix and Ledger's respective Jokers, or RDJ's Tony Stark, or Hiddleston's Loki, or Jackman's Logan. It's pretty decently above average in the genre but I think there's more than a handful of superhero movies that work better by the sum of their parts. I guess ultimately it's subjective, but I really don't think Wonder Woman deserves the mantle of best superhero movie. I think it misses that mark by a fair bit.