Let's see what an Indian Navy blockade would look like
I'll answer in a more appropriate topic, this isn't an economic discussion at this point.
You didn't compare blockade: you compared current fleets.
Blockade... lets write down blockade then.
For example, lets roughly sketch (but more realistic) "Blue" Order of battle.
Forewarning: It's intentionally disconnected from actual IN deployment patterns, as it is only a demonstration.
Disclaimer: this was invented by me, right out of my head, just looking on the map, and taking into account my small knowledge of naval history. Myriads of "small details" may make it completely unrealistic, but let us be frank - I am neither a naval officer nor I am paid to do this seriously.
Overall concept: IN deployment will be as follows:
Forward position - sea denial assets deployed to chokepoints;
Andaman position establishes control over the battle area;
Battle fleet as a reactionary force;
Rear formations exploit local sea control to the fullest. All that trying not to use too much IAF fighting strength (they'll be busier elsewhere), and somehow keeping eye on Pakistan.
In addition, IN is divided into
Eastern(maneuver) and
Western(deterrent) force, as well as units meant to move freely(escorts).
Important note #1: Geography.
Basically our combat theater. Courtesy of google maps.
Basic physical geography:
Indian subcontinent&Shri Lanka are positioned in the middle of the ocean, which is clearly defined by landmass. While India itself may look small on a 1:26'000'000 map, - it's actually freaking huge, with an important consequence of splitting the theater for IN itself into two parts. Additional consequence, often forgotten, is that huge exposed sea coastline is one huge vulnerability, which can be often exploited by units that don't look so grand and cool on 26 mil map. Humans don't live on 26 mil map, we're smaller creatures.
The Eastern part of the theater is composed of everything that lies west from Indochina, Malay peninsula, as well as west, south-west, and south of the ensuing 1st Island chain. Islands and straits east of Sunda are essentially out of practical reach for IN - but also arguably too inconvenient for PLAN.
First of all, this really disconnects two theaters - only leaving few entry points, with huge maritime traffic flowing through them w/o stop. This makes any crossing operations risky.
The most important feature in question for the eastern part is
Andaman and Nicobar islands - located within 1300...1700 km from the eastern entrance to Malacca strait. At the same time, they're comfortably within an unrefuelled flight range from India.
This ensures that the whole length of the passage as well as much of the surrounding sea is one big shooting ground: Indian heavy fighters comfortably reach everything, unrefuelled and with a combat load.
Another important aspect: Islands are numerous(almost 600), stretch over a huge area(Solomon islands-light), and include large and densely populated islands(middle Andaman is significantly larger than Okinawa). Just getting to them will be quite troublesome, and landing =/=capturing.
Western part of the theater(for India), while very secondary in our scenario, has one huge, Pakistan-shaped problem.
The range between two points is such that units in the west can't react in time to problems in the east, and vice-versa. In addition - This time it's actual indian SLOCs(and coast) that are under threat.
Basic political geography:
Eastern part: 1st Chain problem once again: neutral countries(countries of Indochina peninsula, Malaysia) form "Wall" of neutral airspaces. It substantially using some of the most convenient Chinese reconnaissance assets at will - and crucially - all of them that can provide full targeting data by themselves. Air assets are tied to the very same international straits which ships have to use - this both limits their useful patrol range and makes them vulnerable (due to obvious ambush points).
Some are too short-ranged, some are stuck with their operational profile(WZ-13 as a single-use suicide drone doesn't sound too nice).
Furthermore, the same abundance of countries provides a headache of the whole bunch of possibilities to engage neutrals instead of enemies: massive civilian shipping and air traffic, huge scale of fishing activity, and so on. Neutral countries make scenarios annoying for both sides, and favor the side with better access to tactical reconnaissance assets(as well as with better ability to identify targets).
Western part: not much to say again. Pakistani navy almost unavoidably ties the amount of Indian assets comparable with its own size.
This draws quite a lot of forces from the East, and it's actually
here( @Ouagh), and not against the PLAN, where IN really would want to have more area defense anti-air ships. But alas, they can't.
Also, unlike on land and even in the air - India won't be able to settle on just deterring - it needs to somehow be able to protect its traffic. Even if it'll avoid Pakistani waters - it will not become invulnerable, hence the need for continuous escorting. Pakistan also alleviates some of the pain the whole approach creates(its ports can be used for China-bound goods), but only part - infrastructural capacity here isn't limitless.
Honorary mentioning is Djibouti base: it's isolated. "don't let your enemy use your bases against you"(A. Mahan again ;p).
Important note #2: assumptions.
-no third parties, but western powers remain blind to Indians playing sea control games. For example, another Tibetan contingency grew into a full shooting war;
-third parties remain neutral and unoccupied, but also retain their current political stance(Pakistan clause);
-no nukes and counter value, but all other means are assumed to be at play.
(/1)