Those blocks are no more valid than pork is to a Jew.
Alphonse Pace

Then UASF will be a non existent event. The Bitcoin network is run by mining nodes including transactions in blocks and validating them by putting work on them and extending the blockchain. Users agree or disagree if this network is useful for them on the exchange rate by selling or buying the coins which validates or not the value of miners work. There is no other way around.