The limit wasn’t artificial though, it was the number of characters you could send in a single SMS message (160 minus 20 reserved for meta data)

It wasn't artificial. Twitter started as a way to broadcast an SMS text to followers. SMS length limit was 160 characters at the time. They reserved 20 characters for usernames resulting in the birth of the 140 limit.

Not at all, there's plenty of very deep and researched conversions on twitter for those who seek them.

However, a lot of people have already had conversions that were not that deep to begin with, and twitter just helped them get more succinct.

>there's plenty of very deep and researched conversions on twitter for those who seek them

To be fair, that only happens because people work around Twitter's character limit by joining multiple tweets into "threads." It kind of works but it's also awkward and obviously contrary to the platform's ergonomics.

Twitter wasn't designed or intended for deep conversations, though. It's meant for microblogging and posting pictures of your food.