Let's assume that this is a faulty DMS that was slapped together due to imminent threat by state actors. If these state actors were sufficiently powerful, couldn't they instead press ahead anyway with obtaining the developer's private keys, account data, etc., while publicly parading either the real developer (or an actor) in front of the spotlight briefly enough to claim that this was all a mistake? Next, release another series of new versions (with backdoors) that are fully controlled by the state actor under the guise that they're perfectly okay.
Of course, this would itself be easily defeated by either examining the history of the individual who claims to be the developer (if applicable) and through some scrutiny of the new binaries, although I'd imagine the latter would be anticipated by the actors behind the charade.
The closest thing in my mind that this resembles is a warrant canary as someone else pointed out earlier today. I suppose that in effect the DMS and canary achieve roughly the same goal so perhaps I'm just splitting hairs at this point. I also don't see either of these scenarios working perfectly except to warn people who are themselves already somewhat paranoid.
The reason why is quite simple: if a malicious third party were to raid or steal the private key, this kind of deterrent message should act as ample warning not to trust any further releases than what has already been released. If a government agent were to capture a developer and hold him or her hostage to attain the key (and thus release a backdoor), this type of DMS would immediately draw scrutiny to any actor attempting to release a new version that claims differently. If anything, the implicit statement is "continue using 7.1a and do not update beyond that in the event that something newer is offered." In light of the recent audit, it appears that 7.1a is secure -- and as a result, it can still be used for cryptography purposes (however subsequent releases may not).