Nice discussion but there is catch in the story. So called Unified Payment Interface is currently only limited to India since it was tech invented by them and is still not available anywhere else.
However, its going to be available in few other countries outside India after 30th April. There might be some development in the coming days. However, for your theory to work properly you will need the UPI everywhere around the world.
Since bitcoin is already available everywhere it still overcomes the challenges of UPI and is already an upper hand for us. It wont get disappeared just like that considering the millions of confirmation since genesis block.