I looked into the numbers, ignoring the older junk.
- Considering our eastern deployments, by 2025 we can deploy at best 2500 of our tanks in the west, against their to be upgraded 750 Ak-1 standard & 460 VT-4, plus 300 T-80s... not a great enough numerical edge given at present all our tanks are quite significantly outmatched techwise & we have no good plans to. Changing T-72 turrets will bring them to only T-90S level. Arjun Mark1 were competitive in 2005, not anymore. Mark1A is theoretically better but the platform itself has reached its upgradation limit. Both Ak-1 & VT-4 tech match its. It's exactly like '65s Patton-Centurion scenario.
- Same with rifles, we have a better one in Sig on papers, but without sights it's no better than their G3 on field.
- They're getting lots ot great mobile arty from China, more than us. Towed arty may be at a considerable weakness at present or near-future.
So yes, the best option would be as i said, ie, invest in the Navy where were already ahead... Pump money in the Sukhoi upgradation & replacing Mig-21 with Tejas Mark1A... Then wipe out their Navy & AF with our numbers while maintaining static fronts at ground. We can defend with what we got, we can't go offensive.
And that's exactly why i think infantry upgradation is on noone's priority list.
Personal opinion based on my reasoning, but I think it explains what's happening.