-- (Please lets not do the fanboy "Flash is garbage" here - even if you do feel that it was heating up your CPU with ads - it would have taken a lot less than 8 years to fix that then to reinvent everything and find out that money still makes the world go round.) --
They had more than 8 years to fix it on the desktop and didn't. They had more than 8 years to make the Mac version perform at rough parity with the Windows version and didn't.
Either way... "it's fine, we'll make it work well within a decade" is NOT a good message to your users.
Even though my Mac never had significant problems with Flash. I mean - fix what? I don't have Flash installed any more but my fans still spin-up with multiple tabs and overactive pages trying to open a bunch of animated or video tabs.