Comment by JoshM33k

Those types of fragmentation issues never went away, they just changed focus. Whether it is Slack vs. Hipchat vs. Zulip, or WhatsApp vs. iMessage vs. text vs. Hangouts... more options means more (and easier!) ways to contact friends, family, and coworkers, but also means that you have to memorize a "best way to reach me" chart for each individual person.