I can see your point but I think Cantwell is just playing with Doom's long history of always coming back from all sorts of perils since Stan and Jack's days. In issue #6 he should have died in the cold depths of space but we see later that the Ovoids rescue him. Similarly, Rama Tut/Kang just happens to be passing by and sees him clinging to an asteroid in the follow up to him once again being set adrift in the cosmos at the end of FF #23.
I am curious to see a follow up with regarding the situation with Mistress Death. One thing idea that I've been kicking around in my head canon is that for some reason, Doom is important to the some mysterious, unseen forces in the Universe. Sort of like there are Nexus Beings like Wanda throughout the Multiverse but I'm not saying that is his role. In some stories, he's been seen as living far into the future and fulfilling some role either as a destroyer or it's saviour, most recently in Hickman's New Avengers/Secret Wars epic. A later story in Aaron's Thor has him once again surviving in some distant future with the Spirit of Vengeance and the powers of the Sorcerer Supreme. Or maybe it's just that writers like to use Doom a lot