I think this is an excellent suggestion, assuming the post office survives an ongoing calculated attempt to cripple and privatize it. Routing digital payment requests to bank addresses is a natural extension of the responsibility of routing all physical mail to any physical address.
"National Payments Corporation of India (NPCI) is a non-profit set up by the Government of India to facilitate digital payments. They facilitate many payment schemes (like IMPS, BBPS, FASTag, etc.)"
Except that UPI is a payment standard, Google neither has monopoly over it nor the only one payment company who supports UPI in India, there are many others like Paytm, Phonepe, Mobikwik, etc.
Killing it will hurt rural areas, Trump's base, far more than urban areas, where there are other possibilities to get things delivered. If it's destroyed, the guilty party (Trump) will be destroyed, and it will be put back together next year.