No, Twitter has a monopoly on people who use Twitter. If you decoupled the users from the technology (e.g., by way of some common protocol that allows human communication networks to span social media platforms), Twitter would probably vanish overnight (surely losing out to a competitor with an "edit" button).

> Twitter is only used by 22% of Americans as of 2019

In what world is it okay for one company to monopolize much of the communication of 22% of Americans? Especially since Twitter isn't some neatly isolated system, but rather its effects spill over into the outside world; consider how often traditional media cites Twitter (not only with respect to Trump's own Tweets) or even Twitter's role in BLM protests/riots and the Capitol Hill riot. Twitter's reach pretty clearly far exceeds its own user base.

Moreover, Twitter and other social media giants often act in concert, so it's not "just Twitter" or "just Facebook" that we need to be concerned about, but also these giants acting in their mutual interests.