This seems to me more evidence that intelligence is in part a social/familial thing: that like human beings that have to be embedded in a society in order to develop a certain level of intelligence, a certain level of an intuition for "don't do this it will kill you" informed by the nuance that is only possible with a wide array of individual failures informing group success or otherwise: it might be a prerequisite for higher level reasoning beyond a certain level (and might constrain the ultimate levels upon which intelligence can rest).

I've seen more than enough children try to do things that would be similar enough to dropping an anvil on their head to consider this 'no worse than human' (in fact our hackerspace even has an anvil, and one kid has ha ha only serious even suggested dropping said anvil on his own head). If AIXI/AIXItl can reach this level, at the very least it should be capable of oh-so-human level reasoning(up to and including the kinds of risky behaviour that we all probably would like to pretend we never engaged in), and could possibly transcend it in the same way that humans do: by trial and error, by limiting potential damage to individuals, or groups, and fighting the neverending battle against ecological harms on its own terms on the time schedule of 'let it go until it is necessary to address the possible existential threat'.

Of course it may be that the human way of avoiding species self-destruction is fatally flawed, including but not limited to creating something like AIXI/AIXItl. But it seems to me that is a limiting, rather than a fatal flaw. And it may yet be that the way out of our own fatal flaws, and the way out of AIXI/AIXItl's fatal flaws are only possible by some kind of mutual dependence, like the mutual dependence of two sides of a bridge. I don't know.