I fail to see the relevance. Linux never tried to be an 'open source Solaris clone' and of course it didn't die off, in fact, it flourished, which sort of undermines your argument.
> Even more relevantly, IE and Chrome.
What of them? I could see Mozilla vs IE.
> As somebody who has actually produced software for thirty years
Appeal to authority ;)
> but without ever hitching my wagon to Flash like some here
Join the club. I absolutely hated Flash and for many years resisted using it to deliver video.
> I'm a bit more skeptical about the likelihood of taking a gigantic long-lived ball of mud and making it perfect.
Perfect as in 'perfect emulation', not perfect as in perfect all across the board. Having the Flash source would allow the open source implementations to look at how things were done so they can emulate all behavior up to and including the bugs. If Adobe would open source it then they would not have to avoid looking at even disassemblies of the Flash code.
> In particular, security is hard to bolt on after the fact.
This is not about future developments in Flash, it is about digital archeology. If you start seeing it through that lens then maybe you will be a bit more relaxed about it.
Nobody is suggesting that Flash be given eternal life or that we will have another round of Flash content if Flash is open sourced. The sooner it is gone from the web the better. But that old stuff still remains and maybe one day someone wants to review it. That is what this is about. CF people using C64 Roms or Nintendo stuff 3 decades old.
> I certainly wouldn't assume that the maintainers of other implementations would be overjoyed by the prospect.
Did you ask them?
> Just look at how many reimplementations there are of things that were already open source.
So what? Fragmentation is the very power of open source at work.
> I'd say it's unlikely that a significant number of people will work on Flash without being paid to do so.
Exactly. So that is - again - why open sourcing the old Flash player is a good thing.