India cannot produce Entirely T90S locally in case of a war, it will need to import parts of it from Russia.
While Pakistan doesn’t entirely produce Al-Khalid either, the power pack being the biggest exemption, it’s clearly been seen that they’re moving to a Chinese powerpack from the Ukrainian one and have tried to get ToT for said powerpack.
similarly, VT-4 supply to Pakistan will only increase in the case of a war, that’s definitely a strategic advantage because it means Pakistan might be able to procure more tanks in the case of an active war than india, which can build Arjun’s, but they’re not too useful. As for cost, Al-Khalid is the cheapest of the three, followed by T90S and then VT-4.
Moreover, Pakistans massive fleet of Type 59s can be upgraded to AZs in the case of a war as well, though I highly doubt such an option will be considered because the money would be better used elsewhere and they’d need to source foreign parts that were not buying in large amounts anymore.
That being said, india already has a larger armored reserve than Pakistan and said reserve has considerably better Tanks than Pakistans reserve (T72s versus Type 59s and Type 69s, however the Indian T55s are comparable to the Pakistani Type 59s), so we’re currently playing catch up in that regard.
(Pakistans active fleet has considerable technological superiority over the Indian fleet, but that’s just one cog in a massive machine of combined arms so I won’t comment on how useful that will be in the long run, if the supporting arms aren’t as good, then this technological advantage may not mean much)
It will take 5+ years to retire Type 59s and 69s to reserve, and maybe a further 5-10 years to retire AZs to reserve, by then india will start retiring T72s, but that’s all highly speculative.
In the modern scenario, the use of UCAVs makes a significant difference as its an active threat to tanks and other armored vehicles. If complimented by gunships, this combination can become deadly as UCAVs to a great extent perform the role of a CAS aircraft with the armament they carry minus the cannon. While PAA may keep gunships in own airspace, UCAVs can/will cross the border in the event of a conflict. Isn't it a relief that PAF may not be required for CAS.
Then the ATGM support on the ground through TOW and BS equipped M-113s or 4x4 aided by infantry carrying M-113s. This combination of anti-tank capability and holding ground ability by infantry is crucial in capturing territory to consolidate the advance of armored forces. So far neither UCAV, nor gunship or infantry can blitz through enemy lines like a MBT. A UCAV can soften targets by tank plinking but to advance into enemy territory, tank and APCs are needed.
There is another tactic. While UCAVs take out enemy armored vehicles, PA M-113s (ATGM/12.7mm) move in to sweep the remaining area for capturing and holding or chase the enemy. Although MBTs can chase better to cut off retreat but they do need back up by APCs. Some say MBTs are obsolete. In dense AAA and SAM areas, UCAVs may not survive for back to back sorties. UCAVs are more mobile than MBTs, but MBTs can have a high survival rate. In logistics, support, maintenance, the MBTs need a complete setup in the battlefield and mobile workshops.
The factor of artillery remains. Tubed and rocket. Guided, RAPs, anti-armor - all types of ammo. Different targets, ranges, ammunition logistics, OTH fire support. Artillery lies in support, not direct contact like other arms.
We should be talking about wiped about armored regiments, 25%, 33%, 50%, 75%, massive losses, whether AK or T90s or VT4 or T72. Replacements for MBTs in PA are hopeless. Both armies can defend their territories, but its the attacking punch through the enemy lines which starts an offensive into enemy's territory. If the replacements are soggy T-59s then GHQ will throw in reserves. Crews train on T-59 but man VT-4 now, its such a downgrade to go back to T-59s. The slow speed is another bummer. No modern electronics.
I think its the first thrust for armored regiments that matters the most, after that its a strength of replacements, logistics and support to continue an offensive. If the first ones a disaster, then that regiment will be sidelined for secondary tasks. A CV-90 or M2 Bradley like vehicle for cavalry could have an addition for back up if MBTs take bad losses but that 125mm gun wouldnt be there still and thin skin in direct contact may not be the best choice.
All in all, all these arms and weapon systems go hand in hand. MBTs with APCs, SP guns, UCAVs and gunships.