I think it was the inability for GUI's to stay stable. Gnome went off the rails, Unity completely ruined Ubuntu[1], and KDE always felt very cheap and hard to navigate. My opinion, yes, but I always felt the GUI changes in Linux were extremely gratuitous after Gnome 2. Couple this with the fact that for a decade, the actual GUI was tied very, very heavily to the apps. So you had to use Gedit in Gnome, or whatever the…
> Inside, it had plenty of power, an 850MHz Pentium III-M, 256MB of RAM, and 802.11b for wireless networking (if you could find a wireless network, that is). Plus it had 20GB of storage, FireWire and even one USB port.