Skype also has audio and video, with custom codecs even, and p2p, yet it wasn't even close to using the very real 1gb of ram slack consumes
(I'm talking about the old desktop client, not the new electron based one)
(I'm talking about the old desktop client, not the new electron based one)
There's bloatware out there, and this may even qualify, but it isn't just text chat. (Why would you use the desktop client for text chat anyway?)