That is the pretext they are using. Blame pockets of illegal activity on an entire platform, arrest, sanction anyone involved and then assume control over the platform. This type of content was all over Reddit and twitter for years, it was never brought up by them and no arrests were made because they don't inherently care about those things AND they already control most platforms.

But it is easy to gain support for their actions when almost all people disavow that sort of content, and so people will consent to a heavy handed approach that is actually there to ensure only their propaganda outlets can 'disseminate truth'.