Yes and we aren't really comparing with those films now. Its just that "see Dunkirk did only 22mn" is not really a good case to be made.
e.g. Endgame opened to 200mn in US, that would have been great number in isolation, but anyone trying to justify saying Captain Marvel did only 153mn, so 200 for Endgame is great won't be a good justification.
Yeah Warner didn't expect that, neither any of us. That's why before latest COVID insurgence expectations were $40mn, not $90mn.
South Korea can have legs, but WOM is not that great as yet. Yeah it can rebound from external factor like COVID and typhoon, but that's always case of Will it? than When?.