Most overrated and underrated twitter features?

Overrated: audio tweets. Released a little after the riots - people only used them once.

Underrated: sms to tweet. Disabled in 2019 for security reasons- lets people tweet from a text message. Directcast with texts would be cool.

I was responsible for killing that. Was a huge source of security issues and was an old codebase no one knew to maintain and non trivial costs.

“A lesser known fact is that the initial tweet limit of 140 characters was put in place so tweets could fit inside the SMS messages that powered the SMS-to-tweet feature.”
^ is this true?