scroller: you are being disingenious about the sugya in Kessubos. It is a long gemoro where clearly virtually all amoriom believe you must feed your kids. As a matter of fact, they say that it became a “takkanta” made in Usho. Rovoh’s words are only his and actually, tosfos says that one can force someone to feed other kids with verbal pressure and/or a specific set of payments.
But all this is irrelevant. The Rambam (and Tur and Shulchan Aruch)paskens clearly (hilchos Ishus 12-14) that it is an obligation to feed one’s children until they are six and, if you have any money, till they grow up.
AS far as Rav nehoroi- this is a ‘daas yochid” and the gemoro in berachos (35B) is the definite word on this- saying clearly that only a very few people can live without working.