Skype is an 500-lb pig, and keeps getting fatter
This used to be a nice, compact application which did exactly what I needed it for: voice and text chat, with an occational file being exchanged. If I needed to take a peek into the said file, I already had the tools and the knowledge of how to do so, thank-you-very-much.
It is gradually transforming itself into a multi-gigabyte beast, with its own background update service and a tentacle stuck into every conceivable nook and cranny of the OS.
I still run it on my linux box (where it is still reasonably lean, and keept the classic interface thanks to the lack of updates) and on my android phone (but only after digging out an older, less bloated APK) - but it is gone from all my windows desktops, and it is not coming back.