Hard luck, going through the same stuff. They keep on bringing new variants or spacing/sizes without any discussion and keep on increasing the code that needs to be maintained and followed across the app. Then while testing and evaluation goes on to make further changes and ruins the entire process.
Further someone else from other teams might show up and give suggestions resulting in re-creating these fancy designs.
I don't think there's any particular way to stop this because a lot of these designs might be approved by the product/leadership team and further discussions are not fruitful.