That was no idle musing; he had in mind a reversal of the situation.
He put that into action by making a language so embroiled in its own implementation that cloning a new version would be a pointless exercise in failing to replicate the internal details of the original program. That nicely solved the problem of it being hard to port a script.
Then he made it incredibly hard to build. Cross-compiling it wasn't even a thing, and probably still isn't; we just use distro builds that have Qemu.
