First off put the thought that the law makes sense out of your mind. It doesn't.
Basically the outline of the suit is going to be "You always wanted to fire me because I'm black/Latino/gay/old/fat/thin/sick/whatever, so you tried to pretend I was doing a bad job. But then when it became clear I was such a good employee you couldn't do that you pretended it was an economic decision."
Now, this may or may not fly in court, but from the company's perspective it's a crap shoot, since you never know what a jury is going to do. They'll settle if they can. Which means lots of people will sue just looking for free money, even if they know it's all bullshit.
I think anti-discrimination laws are probably fundamentally flawed. I think they should be killed, but with an exception allowing the EEOC, anti-trust or similar to order particular sets of companies to stop discrimination for a period of time if necessary.
Basically the outline of the suit is going to be "You always wanted to fire me because I'm black/Latino/gay/old/fat/thin/sick/whatever, so you tried to pretend I was doing a bad job. But then when it became clear I was such a good employee you couldn't do that you pretended it was an economic decision."
Now, this may or may not fly in court, but from the company's perspective it's a crap shoot, since you never know what a jury is going to do. They'll settle if they can. Which means lots of people will sue just looking for free money, even if they know it's all bullshit.