While I agree that impersonation or platforms showing up first in search results is bad, whether the restaurant gets the full margin is a separate issue and currently correlates negatively.

A restaurant that's being impersonated without any agreement/permission will get the full margin, because the platform has to buy at retail prices.

A restaurant only loses money to commissions when they have an agreement with the platform, and that agreement very often also allows the platform to set up those pages that show up first.

So a law requiring platforms to get permission to deliver might end up with fewer restaurants getting full margin!