Of course some are flat-out lying, because when you have thirty women all come out and accuse him of the same crime, it's easy for a couple extra to hook on to the case in hopes of winning big cash during a civil trial afterwards.
But to say that they are all lying is pretty much ridiculous. Cosby has admitted to drugging women with Quaaludes. It's not impossible that he raped far less women than is alleged, but he's definitely a rapist.
And that's all that he admitted. Sure it's not impossible. But with no evidence to say so, Cosby either didn't forget those women or forgeted them consentingly.
Look at the OJ case. Everyone knows that he murdered Nicole Simpson, or at least had some sort of direct hand in it, but courts were unable to prove, beyond a shadow of a doubt, that he deserved life in prison. However, only a few years later, the guy goes and commits armed robbery. The court of public opinion is often more accurate than courts because people's opinions aren't bound to acquit anyone who is not 100% proven guilty.
Yeah, but in cases like those at least some evidence is presented. Here, it has just been accusations. No police reports (from those cases back in the 80s, I know about Constand), no DNA tests, no security camera footage from more public spaces showing Cosby with the women on the night they were supposedly raped, nothing. And yeah, rape cases are hard to gather evidence for and hard to prove, but that doesn't mean you can call him a rapist because thirty women said he's guilty. I could say he raped me, would you believe me?
The court system in this country is not perfect, but it's better than the alternative, which is the kind of lynch-mob-style kangaroo courts that would be run by the populace, making their own judgements like you said, regardless of things like facts or evidence. If the public were allowed to try people based on public opinion, all the cops that shot unarmed or armed black men in self-defense would be behind bars for life. Every rape accusation, frivolous or not, would result in life imprisonment or the death penalty. It would be a massive loving stuffshow. Facts and tangible evidence come first, every single time. Without that, you don't have order.
A lot of men have been falsely accused of rape and sentenced to life in prison. It's an accusation that almost always has no rebuttal for those who falsely make it, and it's one that can be easily made if you don't like someone and you want to ruin their life. You have to look at cases like this with the highest amount of skepticism possible.