When was the last time a blockbuster flopped this bad both critically and commercially?

I'mm trying to think of some more and but having a hard time typing.

There's about 100 more I could mention...

Demolition Man is a good movie , and it did alright in box office.

Batman & Robin and Godzilla weren’t expected to be critical masterpieces, which is quite unlike Joker 2 (a sequel to a movie that got nominated for several Oscars). Batman & Robin also broke even at box office

"Godzilla" 1998 doesn't fit because it was the ninth highest-grossing film domestically that year and the third highest-grossing film worldwide. Sure, it underperformed domestically, but it made a decent profit worldwide.

On a personal level, it's the best Godzilla flick I've seen, not that I've seen many (and I realize it's an alternative Godzilla).

Expectations were not as high for Megapolis. Joke just a few months ago was projected to open at or near $100 million domestically, and they are heading for $40-45 mil right now

Difference is Megalopolis is a self funded passion project that everyone expected to flop for months now.

Joker 2 was tracking for a $100+ million opening weekend 2 months ago.

Those are all 'fresh' on Rotten Tomatoes whereas Joker 2 is rotten.

Yeah, all I could think of was Terminator Genisys but the anticipation for that wasn't as high as Joker 2, although Arnie returning to the franchise did get fans excited. The trailer however spoiled a big twist and also you could kinda tell it was going to be a crappy cash-grab.

Joker 2 had good trailers but the buzz was numbed a bit when people started finding out it was a musical.