You say that the issue with hiring a housekeeper is that she doesn’t need it, she wants it.
So that’s my problem here. You don’t feel like you need it. That’s great but she feels that she does. You refusing her this because you don’t feel it’s an absolute necessity is plain mean. You’re putting your needs before hers.
Okay, listen. Your wife of less than one year is carrying your child. She does not want to clean. She may not have the energy to clean. Regardless, GET HER CLEANING HELP. Stop getting stuck on your stupid reasoning.
So what you do now is go run buy roses. Then pick up ice cream. Then bring both to your tired wife. As you massage her feet, tell her how you’ve suddenly realized how stupid you’ve been and how getting her cleaning help is your new top priority