Amazon will just sell everything just above the cost of the good and all the small stores will go bankrupt. We seen this with CPG and groceries with Walmart moving into a city.
For huge retailers as amazon it should be illegal to sell things for less than the average price of the cheapest -lets say- 20 stores where that product is sold in the country (with huge penalties for trying to artificially reduce the average price like creating fake stores or bribing store managers)
Thats what MAP was suppose to do. The brands don't want all their sales from one distribution partner because that distribution partner will have enormous leverage.
Where MAP fails is if brands want to different prices globally. This is because items will just get re-imported if they are priced lower in other countries. They want the benefits of globalization which is cheaper labor and materials but don't want to negative aspects which is the same price globally for the product.
They should simply sell parts at competitive costs, but price labor for repairs, adjustments, etc. at a fair rate.
Alternatively, charge a transparent markup in exchange for “free” service on the item should something go wrong.