I don't think you want to be demonstrating harsh punishments. By being harsh and making examples that's how you create a situation like NijiEn. Likewise you don't benefit from terminating a long standing talent after six years, who's still making you at least half a million a year, unless the potential damage due to leaks outweighs not only the income but also the damage to the brand from a shock termination. If you need an example to show where the line is, the Rushia situation is right there and doesn't cost you anything you didn't already lose, and so is the option of a public suspension. I just don't see the benefit in making extremely costly examples.
Of course, that means the leak itself is the point, or the potential of future leaks.