I think that it's manifestly unreasonable to preemptively knock out communications in a large civilian area during peacetime for essentially any reasons; in that same vein, it's absurd to lay blame at the feet of a communications enabler who provides a means for individuals to escape authoritarian suppression of communications.
The only parties responsible for the violence you are implying would be the individuals actualizing the violence, the individuals originating falsities, and the governments who fail to actively maintain peace. The collective failures of all three to restrain their actions amidst uncertain rumors should not condemn the vast majority of peaceable humans from communicating with each other.
Whether freedom of speech should be externally "dictated", i.e. against the laws passed and enforced by an elected (or often not so much elected) local government, is a much more complicated question, but the ethics of providing a pure communications tool (i.e. a tool that isn't directly leveraged by its creators for foreign propaganda etc.) seem fairly clear to me: I think the desire for communication and information of somebody in such a region is ethical; the desire of others to suppress it isn't.
Cutting the internet is an authoritarian move, that’s used as threat on communities (usually minorities).
There is no moral irresponsibility when it comes to giving the general public access to data. The moral irresponsibility here is India bullying a minority population through their nationalist right wing government.
Also my god I can’t believe the pendulum has swung so far the ass of nationalism that it’s not a moral quandary to restore access to communications to marginalized communities.