Oh don't get me wrong - deprecation
is the right move. We are after all unable to simply remove Flash from every website and every user machine overnight.
But right now we're not moving towards deprecation, Flash is not officially stated by Adobe (nor anyone else of any authority) to be a deprecated technology, and new work is being created for it still (with the encouragement of Adobe, even).
Deprecation at the community level will also require us to define replacements and expand the current limitations of HTML5 so that functionality lost with Flash can at least in some way be recovered.
That being said, my ideal solution here is a bit harsher than yours. Like you, I hope all browsers immediately stop executing Flash code without explicit user permission on a per-SWF basis, and I want them to unbundle Flash. The only people who should be running Flash are the ones who have chosen explicitly to put it on their machine.
In any case, my original post was in response to the notion that Flash should be kept alive because of all the old games/animations that have already been created for it - that is IMO a pretty bogus argument for keeping around something so infamously insecure. Flash needs to be deprecated.
Not to mention from a preservation of history perspective deprecation of Flash is not harmful. You can run an old copy of Windows in a VM with an old copy of a browser with an old copy of Flash (and not have any back compat issues, sweet). I do not believe it should be a priority to preserve everyone's ability to view old Flash content without any prior setup at the drop of a hat. If you want to rewind to the mid-00s it's easy enough to get something like this set up - certainly easier than buying your own 35mm projector or microfilm machine like other archival formats.