There is nothing unpopular about it.
Everyone agrees that all the kids in the family watched their father cheat and get away with it so obviously they will think a one time fling is fine.
Having urges is beyond one's control but acting upon them can be controlled. There would have still been scope of revival if it was a one night stand for Paritosh and his other "visits" were to subside a blackmail and not to have flings again.
Also the problem is the hypocrisy of how men can easily cheat as it's something natural for them but for women it shouldn't. More than Paritosh, it was Anupamaa's fake glorification of women that they can never cheat because they value marriage more than men.
Note that no parenting is better than bad parenting. Kinjal was right to decide to cut the cord of letting her child live in a father that thinks cheating is natural.