Cosby never left the plantation. There’s no political component to this. Women have been saying this about Cosby for decades. Several reported these accusations close to the time when they allegedly happened.
This isn’t a big secret.
As to why now, a comedian cracked a joke about this, it got caught in the public wind, and got around. At around that time, Cosby’s publicity people asked fans to create internet memes of Cosby, but took a hit when some raised the rape accusations in their memes.
But for the meme, this probably would not have taken off.
A good friend of mine was accused of rape. Turned out the charges were bogus — made by a woman mad that he terminated their relationship. But the damage was done. He was suspended from his job without pay for several months, and while he returned to work after the charges were dismissed, he did not receive back pay. Attorneys fees plus the lost wages put him in a severe financial bind for a few years afterwards. Also, his relationship with family, friends and co-workers changed. Even though he had been exonerated, there was still suspicion and fear. He passed away a little over a year ago and I'm convinced the stress from the incident shortened his life.
Sure, maybe some of the stories about Cosby could be true. But we also should consider the possibility that at least some of them are not. Regret over a consensual relationship? Vindictiveness? Boredom? Publicity seeking? Broke and looking for a payout? Plenty of other reasons for these allegations to come out now. I expect any physical evidence is long gone, so how will these charges be proven? It's not fair that these allegations may never go to trial, but the suspicions will continue to dog Cosby. I'm sure he's made good money over the years and probably doesn't have to work, but these unproven charges will cost him a great deal in lost revenue and reputation.