I am also really sorry for Osaka but there wasn't some really big incident here. Hell I heard some much worse insults thrown my way from opposing supporters. That stuff happens and professional players must learn to cope with it. I know Osaka is a bit of special case because of her issues but maybe guy yelling that did not know it.
To be clear I am not absolving the heckler but realistically stuff like that will happen often and she needs to find a way to deal with it.
I think she will always struggle with that... She is a great talent and could potentially become a really great champion but if she keeps struggling with situations like this than she will probably not make the maximum out of her career. And as you mention, I already heard insults that were a lot harsher than these.
Professional sports can be ruthless, and at the top level opponents will look for any way to beat you, any chink in your armour. Unfortunately for Osaka, her opponents will always know that she can be destabilised mentally, and I would not be at all surprised if some of them started to exploit this and try to work it to their advantage. Osaka is hugely talented, and the work she is doing highlighting mental health is really important... but the downside is that she is easier to beat.
It was a woman who heckled Osaka, She or people she is connected to probably
had a massive wager on Kudermetova to win! I agree that Osaka and all players
should be able to deal with something like this but I dont think this happens all
that often in professional Tennis