Parler's members are the rejects that couldn't survive on mainstream platforms due to their poor conduct. That userbase just planned and executed an attempt at insurrection against the US government.

The market overwhelmingly has agreed that Parler violated ethical standards egregiously enough that severing business ties is appropriate.

I fail to see the importance of these people's privacy in the wake of recent events. I also fail to have sympathy for people who trusted this hacked-together Twitter clone with their personal information.

Leaking this information sends a clear message: Extremism and violence are intolerable, and every possible means is at our disposal to fight back against it. That includes exposing violent extremists to the light of day.