[godelski]

Yeah so I'd encourage you to write that on the signal forums. The discussions are very one sided. The arguments against deleting are "it's my device, so my data." The people there are very unhappy with the fact that you can even delete now (feature is like 2 months old).

[JoshTriplett]

That argument alone should suffice. Down that path lies trying to lock down other people's devices, people complaining that they deleted a message but others have screenshots, etc.

Once you've sent a message, the message is sent. Once it's on my device, it's mine. If you don't want someone to have a message, don't send it.

[jooize]

I consider that argument unpragmatic. Any recipient can still be made in control of keeping messages they have received. Sender must assume that the message is unretractable, because recipient can record it with a capturing device. If there is zero trust, you must operate by that assumption. If there is non-zero trust there are practical benefits to enabling any party to request the deletion of messages. Whether each party will accept that request is a matter to consider by the sender. Deletion can be per-conversation or per-contact preference controlled to automate, disable entirely, or prompt.

The program can not guarantee deletion, but in practice that is not necessary for it to be useful.

[JoshTriplett]

I'm not arguing that it is impossible to provide a best-effort mechanism. I'm arguing that it's a bad idea for a messaging program to even consider accepting deletion requests by default, because it sets unreasonable expectations.

[godelski]

This sounds like a classical slippery slope argument.

I think many people believe that if you create data it is your data. GDPR suggests that legally we lean towards this position as well.

[JoshTriplett]

The existence of GDPR suggests that people supporting GDPR lean towards that position regarding data held by companies. Leaving aside that not everyone supports (or is subject to) GDPR, that doesn't justify controlling individuals.

There are arguments for addressing the power asymmetry in mass data collection. Those arguments do not extend to individuals communicating with each other, and they certainly do not extend to forcing those individuals to use technological measures that reduce the amount of control those individuals have over their own devices.