I agree that interdicting a single nation's shipping in this day and age would be very difficult and would likely result in significant international outrage.
However, I believe that merely an attempt by India or another nation to do so against Chines shipping in the IOR means China will have to consider honouring the threat with a naval response of their own.
Whether a contingency with India in the Indian Ocean will result in tensions with US or Japan seeking to brew trouble in westpac is a debatable matter, but I think it would be a rather big assumption to think that the Chinese govt would not have a naval response for the IOR ready if their analyses deem the "risk" to demand it, depending on what kind of trouble actually ends up brewing in the westpac during such a hypothetical crisis.
As for the likelihood of a hypothetical IOR conflict with India, I am saying that the requirements for such a conflict on Chinese carrier fighter requirements will likely be complementary with requirements for carrier fighter requirements for high intensity westpac operations involving the US.
This discussion is a bit of a tangent, and it is about what the mission of the Chinese Navy will be, both including carriers and their overall fleet. I believe that going into the 2030 era, where the Chinese Navy will likely end up with something like at least 5 CSGs, they will have two primary missions, that can be divided based on geographical region:
A: deterring and fighting a high intensity conflict in westpac. This will involve all manner of blue water capable ships and submarines (carriers, destroyers, frigates, SSNs etc), shorter range ships and submarines (corvettes and SSKs), and carrier based and land based aircraft, in conjunction with air force, rocket force and the rest of the military overall.
-for this mission, during peacetime I envision the bulk of the blue water capable order of battle to remain at home in westpac to remain as a "fleet in being" and "home fleet". The entirety of the short range fleet (corvettes and SSKs) of course will remain based at home in the westpac as well.
-during wartime, the order of battle will likely remain the same, possibly with some ships from primary mission B operating in blue water during peacetime to return home in the leadup to war.
B: deterring/escorting and fighting a low to medium intensity conflict in the rest of blue water, but mostly in IOR and around the horn of Africa/Middle East. For this mission, only blue water capable ships will be used along with replenishment ships (carriers, destroyers, frigates, SSNs, AORs and AOEs). But the size of the force that is operating in the IOR and the rest of the non-westpac blue waters of the world will depend on the nature of the threat
-during peacetime, I envision that at most an SAG's worth of ships will be permanently round the clock deployed in IOR basically as a slightly expanded anti-piracy escort and naval presence that the Chinese Navy has maintained there for the last few years. I also envision occasional multi-month long deployment by a Chinese CSG or ARG in the region, say, once a year, to show the flag and to maintain familiarity in operating in the area, during peacetime.
-during wartime, depending on the nature of the enemy (whether it is a medium intensity near peer nation state or a more low intensity non-state actor), I expect at most a CSG (or ARG) + SAG to be deployed to the region, depending on what the level of tension is like, at home in westpac. But I expect even during a medium intensity conflict scenario in the IOR, the majority of the Chinese Navy's blue water capable assets and all of its short range fleet to remain in westpac as a deterrence force. Obviously if strategic intelligence and analyses suggests that the level of risk of a conflict in westpac is very high or very low, then the proportion of the blue water fleet that is deployed to the IOR for an IOR-conflict can be scaled down or up.
