one could argue that marketable software legally has to meet different (and stricter) criteria due to licensing (MIT, GPL, and BSD are AS IS licenses), that FOSS do not have to meet.

LOL, only if by that weasel-word "marketable" you mean "sold for business use along with a support contract and/or SLA)." Otherwise, proprietary software targeting consumers has just as many disclaimers as Free Software does.

(Also, I'm not even going to bother addressing the silly biased framing attempting to disparage Free Software as not marketable.)