Who had a bigger downfall: him, Cosby or OJ Simpson?

Good question.

I would say OJ Simpson because he was accused of the worst crimes out of all three.
A double homicide where one of his alleged victims was an ex wife, leaving his young children without their mother, and a young man where both were white.

There was talk of Cosby going back out and doing a tour of shows.
I dunno how true that is but I could see that happening where he would still have an audience out there who supports him right or wrong.
With OJ no one in the entertainment world wants anything to do with him anymore.

Obviously Simpson. Simpson murdered people. Cosby's conviction was thrown out. He's not legally guilty of anything.

Masterson was the only one who wasn't framed by Whitey.

If the Prosecution could go back in time, to 1994 at O.J's trial, they would've thought twice about having a man try on a leather glove while he was wearing a latex glove making it fit tighter than usual, thus, "If the Glove Don't Fit, You Must Acquit" was the famous line stated by the Late Johnny Cochran that got O.J Off Scott free, of course until he lost the Civil trial over this which was sort of sending a message how badly they fucked up..