I don't know how much is in the editing but that video is horrible she comes across abysmally. It's not like she can deny it happened given it's all captured in Hi Def in front of thousands of people. I appreciate sports stars get emotional they have a lot invested after all but the grown up thing to do is apologise as soon as the tempers calm.
The editing is just removing the tennis she sometimes plays in between ranting. It's not altering the ranting itself - that's how she is. She doesn't deny it happened. She claims she has a right to behave like that because she's a woman, "black" and now a mother. She's claiming that because she has a superior biological group identity the rules of tennis (or reasonable behaviour in general) shouldn't be applied to her (or, by extension, anyone else with the same biological group identity).
She sure can play tennis, but she's a sexist hypocritical bully.
It's worth noting that neither she nor any of the people who add their own sexism and racism to her behaviour can provide any support to their claim that "white" male tennis players routinely behave the same way on court and don't get penalised for it. They can't even provide one single example of it happening, let alone evidence that it happens routinely. They're just irrationally prejudiced people making false claims about the group they're irrationally prejudiced against in order to pretend that their own irrational prejudice is somehow justified. Same old same old.
Random example - last year, a "white" male tennis player (Fabio Fognini) was completely expelled from the US Open, fined $96,000 and provisionally suspended for two entire major tournaments for verbally abusing an umpire. Unlike Serena Williams, who was only penalised one game for it. Unlike Serena Williams, he didn't claim his behaviour was a good thing. Unlike Serena Williams, he didn't claim that he was entitled to behave like that because of his sex, "race" or parental status. Unlike Serena Williams, his first response after the match was to publically apologise.
Or consider John McEnroe, the most famous example. He was repeatedly penalised for verbally abusing officials, up to and including being expelled from a tournament. Not just penalised one game.