Generally yes vasectomy is safer. But if they’re planning to give birth via c-section for whatever reason for example, then in practical terms there’s basically no additional risk. Plus neither method is totally effective. So if you can both get fixed you have much better chances of not getting pregnant accidentally.
My partner hates when I open bananas like this because there’s a little dark part of the banana under that end of the peel that she calls “The Ban-anus” and thinks it’s gross even if I pick off that part and don’t eat it.