I've seen it. It was pretty funny, similar to how "The Room" is funny. It's not a "good" film in any sense.
it is divisive and it does absolutely nothing to help tackle racism.
Actually being a "Karen" is more divisive and actively supports racism. It's a real phenomenon where some white women behave in ways that are racist, but because they're not being actively aggressive, they don't believe that they can be called out for their behaviour.
If these women now think twice before they behave that way, I can see how that would be inconvenient for a subset of white women, but it's a net positive for ethnic minorities.