Good take generally but don't agree on the signal point. I very much doubt it's malicious, I think it's a trade off they've consciously made.
Getting family onto signal was easier than it would be to get them on simplex
Discussion
There is absolutely no reason to force phone numbers, they could add the option of username/email. Except for surveillance of KYCed numbers for social graph building.
Moxie's shitcoin in spring'21 was a good indicator the project follows no proper human values.
That's kinda fair, forgot that even existed if I'm honest.
they don't need to be malicious to collect too much useful metadata, just because these are the limitations of their protocol