I mean first to make it an explicit part of their product strategy that the only peripheral connection standard they would support was USB. Now, to be fair, Apple had been in a ghetto of their own making for peripherals with their DIN serial ports and ADB keyboards, but the iMac's total switch to USB happened when PC makers were still mixing USB with parallel and serial ports (and I still have PS/2 and 9-pin DIN ports on most of my windows machines). I don't think it's controversial to say Apple were the first to make a 'legacy-free' computer with the iMac.
Ok I see, good point. Made me thinking: how did Apple got into this position where they could pull such tricks without customers going completely mental but sometimes even rather the opposite: craving for the newer device? I mean, imagine it's the year 2000 and a company like Dell or HP says: 'we drop the parallel port'. Hell would brake loose.
Well, those were dark days for Apple. They were sort-of circling the drain in danger of going out of business. Their market had been whittled down to die-hard Apple fans. So they could do things like drop floppy drives from the iMac when the only alternative to was buy an external USB floppy drive or an external CDRW which cost about $400 at the time. Many of their customers would happily just throw out their old peripherals or jump through the dongle/adapter hoops when Apple would EOL some tech.
