The fate of Symbolics wound up having little to do with Stallman, Greenblatt, or LMI. Sun et al. just blew away Symbolics with the economies of scale of UNIX workstations, and the advantages of LISP didn't persuade many people to go with LISP machines instead. Similarly, Rational Software started out making ADA machines, and only survived and prospered after a total pivot away from hardware and ADA alike.
Hardware targeted to a specific language only has advantage for a little while, until general purpose hardware catches up.
As for the economies of scale of UNIX workstations, former AT&T, Stanford and BSD students got lucky with their workstation startups.