Having a proprietary networking system when no-one else has any networking is hardly a crime. Sticking with it a little too long? Not a crime.
Likewise graphics APIs. (Which platform has non-proprietary 2D APIs?) QuickDraw 3D's problem wasn't that it was proprietary, it was that it sucked.
Likewise QuickTime video. You do realize (a) it was first, and (b) Apple licensed the architecture to the MPEG folk (MP4's container format is QuickTime) and this predates OSX.
I actually had a "discussion" about the whole connector thing with a colleague recently. Eg. In its history The Mac has used three kinds of connectors for mice and keyboards -- a serial connector for the very first Mac, ADB (same cabling as S-Video, so not actually proprietary at all) from 1985 to 1997 or so, and then USB. How's that compare with PC? Go on, I'll let you go Google.
Video is definitely the worst, I'll give you that, but even there it's mainly been a case of sticking to an early standard too long (D25 or whatever it was), the horrific octopus thing (which they tried a second time) and the problems with DVI which aren't unique to Apple.
There was a period when Apple had a weird Ethernet socket that required an adapter for 10BT or RJ45 or Token Ring, but this was because a standard hasn't emerged and competitors generally didn't support networking without an expansion card.
No question Apple has been more proprietary than, say, commodity pc clone makers, but they compare very well to everyone else (Sun, SGI, Commodore, IBM, etc.)