Earlier quoted context omitted.
Respectfully, I disagree. In many cases, things are popular because they are better/easier for a given audience. I'm a smart guy, have managed (and continue to manage) many, many UNIX-based services, and have run several IRC daemons in my life. I still use Slack for internal use, and for our students. What makes Slack (and its ilk, though the title of the post makes a bias against Slack clear) so great is that it's s…
I don't think you're going to find evidence for the argument that IRC is more popular than Slack. IRC's user base is declining, Slack's is growing, and the numbers we have now suggest that Slack is already much more popular.
It doesn't make it a logical fallacy to say something is popular because it's superior for its audience.