I think his point is not that prison is nice, but that 8 months away from a company is survivable for the company. Mothers do it all the time with maternaty leave (and fathers as well).
I cannot speak specifically for Sweden but there are definitely different kinds of prison in other European countries and within the legal system it is sort-of common knowledge which ones are for white-collar crime and which ones are for the really tough guys - and prisoners get sent to the "right place" accordingly.