Besides, there would be quite a few people who'd be actively circumventing any such law if it were enacted, e.g. by hosting the apps in other jurisdictions. And I think that's a good thing! There should be fundamental limits on the power of governance, regardless of how democratic said governance is; and democracies can be no less abusive than other forms when it comes to minorities etc. Or even majorities, when established public mores essentially require widespread hypocrisy - the Prohibition comes to mind. "Think of the children" (or terrorists, or whatever is the go-to political excuse at any particular moment) is not a valid exception.
I agree with your general point except most people in the tech community are not willing to even have these debates. It is often treated as an issue with a single right answer and that encryption can never be compromised.
Removing ourselves from the debate is only going to end up with the decision being made without our input.
But to your point, if the sharing of child porn or other illegal content ever got so bad that something urgently needed to be done I would personally be open to limiting the use E2EE (if there truly was no better option) and I'd assume most people here would agree, although I would argue in many cases it's E2EE that prevents you from becoming a victim of things like revenge porn in the first place.