It’s a tough crowd in NYC. I am probably wrong but perhaps they were booing Serena and her behavior rather than Osaka.
No, the crowd was booing US open officials.
Williams got exactly what she deserved.
She had 2 epic meltdowns.
On my NY baseball chatting site, there is one guy from the city who always goes to the Open and said most were disturbed about the behavior and unsportsmanlike display by Williams. He said he never liked her and now this seals it for him.