Social media platforms (and most modern entertainment, really) fight for your time.
If you’re scrolling Twitter you’re not on TikTok. If you’re playing the Nintendo Switch you’re not on TikTok. If you’re on TikTok you’re not on YouTube.
So what ends up happening is a board of directors ask “why is this user on Twitter and not TikTok?” somebody answers “Well, we serve short videos and they were looking for text microblogs, these are two different categories” and the directors go “well then let’s add text microblogs”.
In fact, the directors could be forced to do so - if they are made aware of one reason their company isn’t capturing even more of the user’s time, but don’t act on it, investors might consider this as intentionally sabotaging their growth.