Why did Madoff suddenly confess all to his sons, who then went to the FBI? Then later, he didn’t fight anything in court, instead he pled guilty. Remorse? No way.
A few months before the confession his wife put a Florida home in her name in a way that would protect it from lawsuits. His statement in court where he went boo hoo has been found to be riddled with inconsistencies and lies. Look, this is a guy who lied to and stole from everyone for decades, a sociopath if there ever was one. You can’t believe a word he says.
So why did he so quickly fall on his sword? Perhaps he perceived an advantage by doing so. It didn’t (and couldn’t) protect his wife and family. The government will almost certainly seize all assets they can find, and his guilty plea won’t stop that.
He did refuse to pled guilty to conspiracy, and again, that won’t protect his wife or sons because they were so obviously involved. So, seems to be, he’s protecting someone else. The questions are, who and why? Another question is, where did all the money go. The answers to those questions probably all lead to the same place.