The Russians will provide the same hardware but a different software. We will likely choose to replace that too, if we are serious about MKIzation.
It's not worth the billions in spending versus investing on 6th gen within the same timeframe.
The Su-57M1 seems to be stuck with 177. They are pushing this engine to the IAF too, which they definitely will not bite. And the twin-seat is expected to fly soon, but will take 4 years for certification followed by 3 years of MKIzation and 3 years of production. So 2037 for an operational jet, the same time it will take GCAP to enter IAF service. Or around 2034-35 for a direct import. The Americans and Europeans will definitely offer an alternative to the Su-60 by then, even if we don't enter their development programs.
S-70 can also be MKIzed alongside Su-60, but we need a more advanced variant.
The 57MKI and S-70MKI will the best eventuality for us at the moment, but the cost of lethargy and falling behind throughout the years must be paid. I think the IAF should induct the single seater 57s, it really seems like the best overall bet. In order to develop a 6th gen, we need to have a 5th gen of some sort. Europe can make the jump from 4.5 gens to 6th gens because they've got one of the most advanced aerospace complexes and weapons manufacturers in the world, India does not yet possess such production capabilities, which is our downfall.



