Earlier quoted context omitted.
The best feature of flash was that it was so easy to disable. Because 99% of the use was annoying ads that pinned your cpu at 100%. And that was Jobs argument, that it was too resource intensive. Predictably though, now that annoying crap moved to "newer" tech (javascript) and now we can't disable it as easily or without as little consequence. Just as resource intensive though...
I never bought the benevolent technical angle for not supporting flash. I'm pretty sure Apple strategists knew the value of the gate-kept platform, the app-store revenue stream. The pivotal point was that flash would break this stronghold by allowing rich applications that are reasonably self-publishable. (Excuse me while I go rinse that sentence out of my mouth)
Even AIR apps - think Electron, an application shell for Flash apps - were on the edge of usable on desktop Macs of the era.