I got an account with Twilio and have gone through at least five different softphone programs, none of them really work correctly.
Some of those programs (e.g. Zoiper 5) suggest a list of sketchy-looking vendors, maybe they work better than Twilio, but the domain names look scary, the web sites 404, etc.
Why is that anything based on open standards seems designed to exclude people?
I've had some of this with my google voice number too but it has gotten much better recently (before I couldn't even use it with Signal), however I'm not sure what the state of using twilio for this is.
There's no customer service to social engineer.