Newsflash: e2e encryption is used to send content that stands to gain most from using it.
The problem is that "content that stands to gain most from using [encryption]" also includes activists protesting authoritarian governments, or even government officials themselves who don't want to be spied on by their rivals, or victims of stalkers and domestic violence.
I have no doubts that the big companies which this seems mostly for will be doing everything to decentralize and remove themselves from the problem citing "systemic weakness" and then doing nothing for the government.
ASIO has to provide statistics on how many notices they issued in their yearly reports. In addition, recipients of reports are allowed to provide statistics about his many reports they've received. See s317ZF.
> I have no doubts that the big companies which this seems mostly for will be doing everything to decentralize and remove themselves from the problem citing "systemic weakness" and then doing nothing for the government.
Except that Apple (and other such companies) have explicitly designed their e2e systems in a way that they could be backdoored (users don't need to sign new identities with a key, so Apple can add a new one -- which is how the device adding feature works).
In addition, many such companies have the ability to provide a single backdoored binary to a single user. This, according to the legislation, would not be a systemic weakness. There is work you could do to make yourself resilient to company-wide sabotage but no company I'm aware of is doing it.
EDIT: Okay, that came out more snarky than I wanted it to. On the one hand, you are right, of course: Provide a secure, encrypted, easy-to-use means of communication, and people with something to hide will use it. If I wanted to download or spread child pornography, I would not do it via an unencrypted channel, either.
On the other hand, your comment might be read by some to mean that you think encryption is the problem. And I think, by the time somebody posts a video of a child getting raped to a WhatsApp group, the problem has been around for while and is not going to magically disappear if WhatsApp were to remove end-to-end encryption from their service.
And child pornography, understandably, provokes strong emotions, which is why politicians and law enforcement officials eager to push more surveillance or censorship like to use it as a reason to push their agenda.