This happened around the same time mechanical keyboards and floppies were being phased out in favor of cheap membrane keyboards and liquid-impervious CDs. This was a progression throughout the '90s starting with the end of the IBM PCs and PS/2 machines in the mid '90s - replaced by cheap clones with even cheaper keyboards and CD-ROMs - to the introduction of the iMac in '98 with its (terrible) membrane keyboard and no floppy drive. Casual computing was pretty mainstream after that.