It’s more than just a grading system, there’s some hardware minimums for battery life/durability etc. and a clause for repairs regardless of the grade:
They must also ensure that spare parts are available for up to seven years after the product has been sold, offer at least five years of software support and provide professional technicians with non-discriminatory access to repair software.
It’s more than just a grading system, there’s some hardware minimums for battery life/durability etc. and a clause for repairs regardless of the grade: