Making fields required in Sanity schema using a validation rule

Is there any way to make fields in your schema Required by default? 90%+ or so of our fields should be required, and we’d rather do something like

Rule.optional()

for ones that are not

No, but since the schema is just javascript, you can programmatically add the

required

validation rule by using a function to assign it to the object containing your schema.
Not quite default, but not too much overhead!