the apple I was very much not that, being built from entirely off the shelf parts and having the source code available for the closest thing to an operating system as it had (wozmon)

the apple II was a slight bit of a setback but it was very much still an open platform, with a very good reference manual written by Woz himself. it even had fully commented ROM listings. I don't know enough about the III to comment on whether or not it was as good in this regard but I suspect it wasn't since it wasn't so close to the hardware like the IIs

then came the Lisa and while it wasn't as bad as the Mac it still wasn't great, and then the Mac killed any hope of hackability

True, but to each their own. There was trend line towards usability. I would say the Mac was a big step towards where they were going.

If you want hackability there were other choices. Usability was there focus. Having a floppy disk was a major advancement even though a cassette tape was technically usable.