Not quite. There are two standards for the statute of limitations regarding fraud. For an individual, it's five years from the time the fraud is discovered. So if after ten years you ask your snake oil salesman buddy for the return of the investment you made with him, and learn he was running a Ponzi scheme and can't give it to you, you can still sue him.
Until challenged, the SEC used the same standard. The Supremes have denied them that, ruling that they have far greater investigatory powers at their disposal--including subpoena power--and so should be able to identify and move on fraud within five years.
I agree. Perhaps this will free up time and staff so they can go after crooks for things they've done recently, not years and years ago. It does take time to prepare a case, but it doesn't take a decade.