This is effectively already a thing in most US insurance markets. TDI (Texas) requires $25k minimum coverage for property damage, so in general this is what everyone is going to have.
If your car is worth more than that and someone runs into you and totals it, you are ~fucked unless you have additional un[der]insured motorist coverage on your side. Suing someone for the difference is a 10/10 nightmare experience. Many people who are driving like ass also seem to have really bad financial situations. There is such a thing as being so poor that you are judgement proof.
The overall effect of this is that drivers of high value (i.e., luxury) vehicles typically take it upon themselves to ensure the safety of their property. They don't make it the problem of everyone else. If their Faberge egg of a lambo gets wrecked, they understand the other parties probably aren't going to be able to replace it. Certainly, follow through with everyone's insurer and wring every policy dry, but the rest is up to the presumably wealthy luxury vehicle owner.
If you are driving a luxury vehicle and cant handle the risk of an underinsured driver totaling it, you should question if you can actually afford the vehicle.