His likelihood of re-offending is low because he now has a near universally bad reputation and so is much less likely to be trusted with other people's money in the first place.
Whether that means he should have a shorter sentence depends on the purpose of criminal sentences. If the purpose is punishment or deterrence, re-offense probability isn't as relevant, but if it is merely to protect others while he is put away, it is the most relevant consideration.
Adam Neumann _should_ have an atrocious reputation given how he treats other people's money but VCs seem happy to fund his new adventures (presumably assuming they can still make money on the way up before the bust).
There would no doubt be people happy to give SBF the funds to go fleece a whole new herd of victims on the off chance he got away with it enough to make the number go up.
Whether that means he should have a shorter sentence depends on the purpose of criminal sentences. If the purpose is punishment or deterrence, re-offense probability isn't as relevant, but if it is merely to protect others while he is put away, it is the most relevant consideration.