We need subs for secondary strike. AC are just a show-off which powerless Indian govt. would never use.
I think that is a bit too harsh.
To think over a few things:
1) Why did the PLAAN claim that they can shut India up with 10 subs? I mean why did they not rely on their surface fleet? What reason was given to them not to think about that?
2) Given that India has a big coastline with hardly much presence of any other Navy nearby unlike the much smaller South China Sea, where you can find some very powerful navies. How many Indian subs could counter-shut-up-china, similarly.
3) The sea lane from Persian Bay and Suez to Mallaca is probably the only sealane in the world where only one Navy has eyes on both ends. All other sea routes require more than one Navies, often adversary or at least a bunch of navies have to gang up together as allies to police it. In such a situation at least 3 ACs on call seem pretty justifiable. Couple that with the Indian Navy's understanding that for a carrier it makes sense to have 30+ aircrafts to be effective as a strategic asset.
4) In such a situation how many subs would actually be required. My long term guesstimate
=>5 SSBN
+ 5 SSN/SSK to protect the SSBN
+ 5 / 10 smaller SSKs for shallow water ambush in IOR.
+ 7 SSN for open ocean duties, protecting CBGs and ambushing in SCS
+ 8 SSGN for SCS counter-patrolling
= totalling say 30 to 35 subs.
5) What is the budget available.