I didn't watch it, I've used simplex... Yeah that's an awful argument, but the tool is interesting.

What I find most interesting about it is, it's kind of like signal but with a random and rotatable phone number. If you hypothetically had your "phone number" leaked or started getting spammed on it, you just regenerate it, your existing conversations get the updated phone number and continue to work while new conversations can't be started with the number you just threw out.

You can also create different profiles for different situations (these have different phone numbers, names, and photos associated with them), e.g. you could have one for people you meet online vs in person vs in your job.