even if the husband doesn't want one. Do you disagree with that?

In fact, I'm sure of it. The ruling protects a resident of the place's right to allow a search without a warrant, even if another resident who has been arrested refuses such a warrantless search. It's an equality thing. It's not permission to search places without a warrant on a general basis.

and an erosion of fourth amendment protections.

who live in a residence as equal. A resident can allow police to search if another resident has been arrested, under this ruling. Why should a resident be subservient to the wishes of another resident in a situation where the police have arrested the other resident?

This will affect many situations, including domestic violence situations. It does not affect the basic rights under the 4th Amendment. Instead, it recognizes the equality of residents in a place.

because if the objector is still present, then the objection prevails.

Saying that an objection to searching one's residence should matter even in that person's absence does not make the other resident subservient. That claim is ridiculous, since the other resident could cooperate in a myriad of ways if they want to. Not having one's home searched is not a violation of one's rights.

As to whether this affects the fourth amendment, I agree with the court's wisest voice, Ruth Bader Ginsburg, who wrote the dissent.

Having read the article, I also know that Ginsburg, Sotomayor, and Kagan were the dissenters.