That was because Twitter gave them out en mass as a marketing ploy (growth hacking.) They literally gave them out to every newsroom for every writer, using the media outlets themselves as marketing engines to get their writers to post content. And the journalists and politicos all being on there made Twitter relevant. So it was a nice network effect.

Now we understand that the whole thing is social media hell. Just looking in the feed occasionally makes you so depressed about humanity. (But it is all performative as it really affects my life zero.)