The DCU's rocky first decade had its ups and downs, but the fact the entire franchise didn't even get a sequel has to be voted as one of the most bizarre, especially when considering how popular Man of Steel continues to be today.
Ben Affleck was immediately drafted into Batman v Superman: Dawn of Justice, which triggered directly the Justice League conflict. Another Henry Cavill solo film popped up occasionally, but it never was officially released.
The first trailer for Michael Shannon's General Zod and putting him against a Kryptonian who isn't Kal-El has inevitably ruffled some feathers, since Zack Snyder's origin story for the DCU's iconic Big Blue Boy Scout is already being used as a weapon to destroy Sasha Calle's Supergirl.
Given the buzz surrounding the first-look footage, The Flash had a lot of expectations to live up to. For the most part, it lived up to them and then some, but there was always going to be a vocal band of detractors ready to pounce.
In fact, they'd already been sharpening their knives for years, so there was no other outcome than negative comparisons to the SnyderVerse.