We shouldn't cherry pick only the examples which support our position. E.g. Allegro Common Lisp has traditionally been about as unfree as possible (e.g. $$$ required to distribute solutions to your customers (for the Lisp runtime)) and it's still around. LispWorks is three years older and is still around.
Also, would the MIT Lisp Machine system or Genera have gotten as good as they did as fast as they did without outside funding (government and VC respectively)?
Or look at the failure of GNU to produce a kernel.
My general point here is that all this is much more complicated that a simple "free survives, unfree doesn't" ... although I'd need a few good examples of unfree dying to round out it out (good as in perhaps "was big, then totally failed").
"E.g. Allegro Common Lisp has traditionally been about as unfree as possible (e.g. $$$ required to distribute solutions to your customers (for the Lisp runtime)) and it's still around."
Franz started only a few years after Symbolics. I believe one of the key reasons they're still around is because their Lisp system is easily portable.
"Also, would the MIT Lisp Machine system or Genera have gotten as good as they did as fast as they did without outside funding (government and VC respectively)?"
Stallman was totally right about Symbolics though - they took all of their Lisp work and most of the Lisp community to their grave. There wasn't a lot preventing them from making their software more portable or open, but they made a business decision not to do that, which proved to be disastrous in the long term.
"Or look at the failure of GNU to produce a kernel."
That's because there's already other, better Free Software alternatives out there. Why work on HURD when you can work on Linux or one of the BSDs? And it's important to note that it's a continuing failure - because the project is Free Software, people can continue to work on it if they want.
Symbolics also had developed a portable Lisp, but closed it. They developers then develop it externally, it was developed and sold as Lucid CL. Lucid CL was highly portable, but the company also did not survive.
Symbolics' problem was not that their software was not portable. Open Genera is a VM and ran on DEC Alpha, it would have been possible to port it to other 64bit machines.
But the business went away. The thing was too costly. It was also not just a Lisp implementation, but a portable OS. As an OS it simply did too much: own networking, own window system, ...
The reason why Franz is still around and Symbolics' is not, is not a question of portability - it is because Franz' Lisp is just a Lisp implementation and concentrates on that - where Genera / Open Genera is an OS, which simply does too much. Why run a TCP stack in Lisp on a machine which already has a TCP stack? Why run a window system on a machine which already has one? Plus the rest of the machine does not benefit from that. If the other software could use the Lisp TCP stack, but it can't.
The Ivory is a language oriented processor - not a computer. It's a CPU, a chip. Where is the difference? Open Genera also does not emulate an Ivory-based computer, but the processor mostly. It emulates the instruction set.
Also, would the MIT Lisp Machine system or Genera have gotten as good as they did as fast as they did without outside funding (government and VC respectively)?
Or look at the failure of GNU to produce a kernel.
My general point here is that all this is much more complicated that a simple "free survives, unfree doesn't" ... although I'd need a few good examples of unfree dying to round out it out (good as in perhaps "was big, then totally failed").