Correction: USB was supported by Apple for the PCI Architecture, but not the older NuBus Architecture. It was an open standard designed for use by ANY computer, just like SCSI.
There's no technical reason Apple couldn't provide support for it for the older NuBus Architecture. But they wanted people to buy new Macs, not hold onto the old ones a generation out of date! You can't really blame them, they were and are in the business of selling newer, better, faster just like any other company.
USB is pretty much the same I/O model as ADB, it's just designed as a better general purpose peripheral bus as opposed to the underspeed, underpowered KBD/Pointing Device oriented ADB.
Hot plugging and seemingly unlimited addressing capability is pretty high up on the better'n ADB list as well.
There's no technical reason Apple couldn't provide support for it for the older NuBus Architecture. But they wanted people to buy new Macs, not hold onto the old ones a generation out of date! You can't really blame them, they were and are in the business of selling newer, better, faster just like any other company.
USB is pretty much the same I/O model as ADB, it's just designed as a better general purpose peripheral bus as opposed to the underspeed, underpowered KBD/Pointing Device oriented ADB.
Hot plugging and seemingly unlimited addressing capability is pretty high up on the better'n ADB list as well.