So I understand culturally, dogs are not exactly popular in certain areas of the Muslim world and there are certain narrations that appear to be against dogs as pets, but are there not narrations which also seem to suggest that it’s not such as the person being forgiving for giving a dog water or in the Quran where the Sleepers in the Cave had a dog (and it does not explicitly mention it was a guard dog) nor the fact that the Quran never condemns dogs either.
Because of this, do the four madhabs have different positions on the permissibility of keeping dogs without a “purpose” (I.e. perhaps having a dog as a companion or for therapy for depression). Sorry for the long description but I hope it helps to assist in answering the question.