D&D 5E (2024) Changes to the Command spell and its use at the table.

[DEFCON 1]

Well, Sleep plus coup-de-grace or double-tap has been very efficiently killing things since 1974, so I think the precedent is solidly established.

That's not the spell killing the person... that's other people doing things after the magic has been cast. You need the right combination of attacking character, no other enemies in the way to stop the advance, and low-enough hit point level of the sleeping creature to possibly assure an insta-kill in that case. As opposed to Command sending someone off a cliff and insta-killing most non-flying creatures. There are enough other steps required in the former that I can accept the possibility, as opposed to the rules interpretation of turning the creature mindless and with no sense of self-preservation on the latter. But that's just me.

 

[Reynard]

There is no decision point in the spell's description. It's intended, I think, to be weighed against forced movement. Given you don't need to even understand the command spoke, and it's a compulsion, I just don't see the creature having the option to think "But I might die and I need to avoid dying" in the spell anymore. They have the option to flee away from you by the fastest available means. Jumping off a cliff would be the fastest available means, if the cliff drop leads them away from you.

The spell does not say anything about changing the creature's personality or awareness or anything else. It plants a singular, specific compulsion in the target's mind. The target then follows that compulsion as if of its own free will.

The flee command requires it move away from the target the fastest way it can. That's it. As long as the creature follows that directive it can still pick its route and method.