I was encouraged when I attended Signal 2018[2] by twilio product and technical managers who intimated that such personal "utility" uses of twilio were favored by the CEO (Jeff Lawson) himself.
Everything you need to know about how this has turned out - and which direction the company is going - can be imparted with two points:
1) Twilio straight up refuses to put an email verb in Twiml. This sounds like a nerdy, nit-picky point from my own personal use-case (and it is) but it's the most dead-obvious thing in the world, is technically trivial, and would make so many use-cases a world easier than they are.
Instead of adding an email verb to twiml (so you could, for instance, cc: an email address with emergency SMS alerts, or perhaps cc: yourself a log of all received SMS) they chose to buy an entire email company. Now you can create these use-cases provided that you sign up a sendgrid account, and tie the two together with code hosted at a third party and blah blah blah.
The reason they did this is providing telco utility tools is not interesting. Customer engagement at scale (or whatever bullshit) is what is interesting. Managing high value interactions. Whatever.
2) Q1 of 2021 they crammed phone only 2FA down the throats of all account holders. You may say "you can also use authy" but, of course, the initial setup of authy requires a real mobile number[3] and you can't log into twilio to enable authy without providing a mobile number first.
So, if you're planning on moving your telephony into the cloud, you can't - you'll need to tie real phones and SIM cards to these accounts. Have multiple twilio accounts ? Congratulations - you can either be super sloppy and share your mobile SIM across all of them or you can buy three phones.
This is for your security. Total bullshit.
In reality, twilio has a massive spam/scam problem that is almost unsolvable. I don't envy them in this position. However, instead of solving this problem, they have decided to just throw sand in the gears and slow down the scammers by demanding that everyone prove a SIM identity. This doesn't bother most users because they aren't, ironically, trying to shed SIM cards by moving their telco infrastructure to twilio ... but it fucks my shit up immensely.
Which is what happens when providing telco utility services has no path-to-unicorn and you need to turn yourself into an "engagement platform" that "enables customer interaction" for "high value use-cases".
[1] https://console.dev/qa/rsync-john-kozubik/
[2] "peak twilio"
[3] Which is so ironic since, in almost all cases, twilio numbers are NOT mobile numbers and cannot be used for "proper" 2FA since they cannot receive SMS from short-codes. So twilio demands a telephony use-case that they, themselves, cannot satisfy.