One rotten regulator doesn’t mean you get to view the entire Indian regulatory environment as unreliable though. It’s the 4th/5th largest financial market in the world.
To say it plainly, SEBI has been exposed for their selective enforcement on high-profile entities. If Jane Street’s in trouble with SEBI then it’s only because they failed to secure the same privileges as Adani, or Karvy, or Ramkrishna, or Sapre, or Kamath.
A market being large doesn't mean it has large participants.
But even then (and as seems to be the case in this instance), the market might have large participants because they are the ones doing the gaming, and are therefore happy to participate (even if trust is low).