RUD is very much a euphemism that has I guess drifted a bit from it's initialism; I'm pretty sure in this case the disassembly was planned and the survival case would have been unplanned.
I take your point, but they're not planning for a launch failure even if they're pretty sure that's what's going to happen.
What happened when most of the mass of a Space Shuttle launch hits the ocean: that's an RPD.
If you’re not planning for failure modes you’re not engineering correctly.
Sure but "lithobraking" takes too much space in a tweet.
I like reading Musk's tweets when he talks about something he knows (e.g. engineering). I don't much like them when they're ignorant and irresponsible commentary on Covid-19 (something he knows less about than even most ordinary but interested people, seeing as he wouldn't have the time to follow much expert commentary), or when he's sharing his puerile taste in humour or music or literature etc (although, to be fair, it's his personal account so he can share what he likes).