They've got a lot of attempts to expand to similar markets, but the problem is that most are second class.

Twilio is the market leader for developer SMS, and voice.

They are not the market leader for any of the other categories that they are trying to expand to.

As someone looking to work with both programmable video messaging and SIP trunking in the very near future, can you name competitors that do it better?

Look at bandwidth.com for SIP trunking.

Edit: if I recall correctly from many years ago, this is who Twilio uses for their US telecom/CLEC interface.

Edit 2: yep, bandwidth.com now even competes against Twilio: https://getvoip.com/amp/blog/2016/06/01/twilio-alternatives/

It doesn't matter. Pick a competitor at random and the competitor will be 100X cheaper.

Twilio is good at one thing. And that is the developer experience.

If you are willing to pay 100X the price, in order to have awesome documentation, then Twilio is the right solution for you.

Otherwise.... Well.... Anything else is probably better.

100X the price? When it comes to SIP trunking at least, Twilio is one of the cheapest[0] if not the cheapest pay per minute provider. Compare with Flowroute[1] for instance, another popular SIP trunking provider, Twilio is significantly cheaper, especially on origination.

[0] https://www.twilio.com/sip-trunking/pricing [1] https://www.flowroute.com/pricing/

If that's true, it's hard to imagine why anyone at Uber's size is still using Twilio.

Because big contracts give companies leverage for discounts. Netflix, for example, pays way less than AWS on demand pricing.

Not yet.

They bought Authy as well.