Didnt the similarly shot sneaked out set snaps of Heath Ledger as the joker also cause a lot of negativity, but worked brilliantly in context ?
Appreciate it wasnt a spandexy rubber suit but still...
It's not quite the same though.
Ledger's Joker was a replacement that was long time in waiting. Everyone was just waiting on them. Here, an existing and generally well liked Superman and actor was replaced unceremoniously very recently, and the facts of what happened that lead to the replacement has put a very scummy shady light onto the current teams (Gunn). Leaving fans non plus'd over the matter, where unless if Gunn's version meets or exceeds Cavil's Superman, it's going to get a hard nope from very harsh comparisons. This was stated a long time back and it's playing out exactly as predicted.
Ledger's Joker was also not the center of the film universe and would not be setting the tone of that film universe either. If we look at the Joker film itself, that's fine as it set the tone for that universe there. Here, it's replacement Superman (for a replacement universe), but it's highly disappointing because of David's costume being so ill fitting and looking really off. CGI can't fix everything and if it was needed to fix something like that, you wasted the money doing so getting the suit in the first place; just put on a motion capture suit instead.