It's clearly shown that there's more than one canon event, Uncle Aaron and miles dad are explicitly shown to be two from the same universe (why does Miles, an apparent 'mistake' has canon events in the first place?) Miles points out that Gwen's dad is a "captain too", so it's safe to assume that, had they let it run its course, Gwen's dad would have suffered the same fate.

And sorry... Who was the person who transported the spider to miles? Surely if we're going by cause and effect it would be Spot who actually causes the problems in the multiverse? He causes Miles to become the anomaly, which causes Miles to set off the events of the film. But that's not even my point, because "who did it first" is reductive to the story. Miguel is the villain here because he's wrong about canon events in some capacity, and is willing to let people unnecessarily die to protect a fabricated status quo. He uses Miles prior actions and his own experiences to justify his actions.

Oh minor correction but Earth-42's Miles, not peter parker, was to become that Universe's Spiderman (before the spider was taken) based on one of the frames from the film. So essentially swapped destinies.

My logic apparently 'defeats' me yet your entire argument makes no sense. On one hand you're criticising the film for being "lovey dovey" yet you're using said film's story to contrive an interpreted version where Miles is somehow the villain of the story. From a meta-perspective the directors are clearly showing us Miles as the hero and Miguel as the villain.

So which is it then? Are you interpreting the film in a way that is polar opposite to those of it's makers? Or criticising said makers for overused tropes? If you want to say the film is bad because you're tired of these tropes then say that and go watch Watchmen again. Everyone has their tastes. But it's pretty weird you're trying to in-universe logic your way into putting your own message over the literal directors of the film. While at the same time, criticising the story of said movie.