I don't blame Sentry. FOSS is a fine ideal for hobby and academic projects, but it doesn't pay the bills. 36 years on and the most successful business model for FOSS is to convince someone rich to lose money on it. (Cf. Gilmore at Cygnus, Shuttleworth at Canonical.)

I do wish more companies would use these kinds of "Doom clauses" and contribute old software to the commons once it's no longer commercially viable.