TP & SK also deny *G in Y access to contract lounges, so UA's move is nothing new. The so called 'change' to *A rules is also not that significant. The bloggers are just blowing this up. If a *A carrier didn't want to pay for contract lounge access for *Gs, it was within their right.
AI only has their own lounge in DEL and JFK T4, the rest is all *A partners or local contract. Curiously in many airports where they could use the *A lounge facilities (VIE, ORD T5, EWR B, BKK, etc) they have contracted with others.