I think it seems low because of the magnitude of the crime. Also because we punish more violent crimes with very harsh sentences including charging non-violent perpetrators with violent crimes(Felony Murder).

Add in the desire to be seen as doing something with sentencing inflation and your get multiple hundred year sentences.

At first I felt that 25 years was short but thinking about it, he will be ~60 when he gets out... so maybe not too short.

if he does 85% and after accounting for the year and a half he’s already been in prison he’ll probably get out by 50

Part of it is that he took it to trial. He likely could have negotiated a deal for single-digit years if he had admitted guilt and cooperated.

I don't think we should pressure people into admitting guilt, but cooperating could be important. What more should he have done to help the people affected by his fraud?

I agree we should not pressure it but if you are guilty and caught with your hand in the cookie jar, it could be your best option. A good attorney will advise you if your best course is to minimize the damage by accepting a plea deal.

How much Bernie madoff got?

Madoff spent ~12 years in prison before he died at 82.

They gave him a 150 year sentence for a crime on par-ish with SBF's crimes, because at 70 there is little difference between 20 years and 100 years, so you may as well go for the shock value.

He was already old so he was going to die in prison whatever happened.

150 years - of which he served 12 years before dying in prison.

150 years.

150 years