[observationist]

Microcontrollers and software for consumer PCs and the like could have been produced, probably, but there are a lot of areas of deep specialization. You'd have had to bring together all sorts of different disciplines and technologies the old, hard way - universities and libraries and researching manually. The internet allowed all of those things to coalesce easily, and novice level people gained access to high quality information and research at the click of a mouse.

The patents, compute, research access, and dozens of other relatively small barriers created a thicket of challenges and no obvious way to reconcile them, even if you had all the right ideas and inspiration. I think the internet would have been needed in order for all those ideas to come together in the right way.