An Indian strike on China when China is fighting the anglos would be intended as a crippling strike, such that the Indian action allows the anglos to win.
This would be a cynically risky scenario to allow because we lose our own whilst also being direct combatants.
China would have made preparations well in advance to deter and prevent this kind of action, as there is no upper limit on what could and would be selected as a target. Civilian infrastructure would be a given, if in the Indian mind, it gives them a chance to end the war and become the "2" in the new G2.
Destroying India violently also offers no real benefit to China - the market is destroyed, and the humanitarian crisis could be used by malicious third parties against China. It's not like we need the land either.
In times of war I would expect Indian propaganda to solidify national unity, so avenues for a targeted attack that rekindles political / religious / ethnic fault lines will be limited and harder to exploit. The environment also may not be permissible for intelligence 'pre-work' to enable such avenues.
On the other hand, if the Indian attack is pathetically weak, it would then be hard for China to justify a crippling strike in India, so again, we incur damage for little gain.
There is a non-zero chance that the contest between the US and China transpires without any hot war or direct regional action; this is the angle China is prioritizing.
Once the balance of power is lopsided enough, I would expect the Indians flip to China, cowering and begging and calling "Saar", after which internal influence + Pakistan + Bangladesh can be used to slowly return India to individual religious and ethnic blocs.
The plotting and scheming will still be there but much weaker, however can be used as a blackmail tool.
This way the market survives intact, the combatants are proxies, the action occurs entirely on the 'away field', and China still has plausible deniability. Clean sheet all round.
