Not only is If all humans >1 years old disappeared, would the rest reboot society? beyond absurd, but OP is actively defending it.
Other than down votes, is there any other action to take? Maybe it's Too Broad, but the answer is pretty obvious.
This reminds me of something I wrote in another meta post.
Your good point is that, while most people, perhaps, can't solve that ergosphere problem, most people can solve basic 4th grade math. But, just because most people can doesn't mean everyone can. The conclusion is that we should not run people off the forum for asking 4th grade math questions. If they legitimately need help with 4th grade math for Worldbuilding puroposes, we should give those question equal time along the near-impossible hard-science ones.
Sort of the same logic applies here, in my opinion. The user in question hasn't demonstrate otherwise that they are a troll. Plenty of people probably have zero experience with children under the age of 1 year old, and don't know what they can or cannot do. If you've never met a zero-year old, and a youngest or single child may honestly never have, then you might not know much about it.
If someone doesn't know as much as you, it isn't nice to assume they are troll. I prefer to give the benefit of the doubt to people. There are some rare cases where a question is pretty inane, but doesn't trigger any of the close reasons. In that case, the only real action is to downvote or answer.
There are several options. In the immediate term, as soon as a trivial or "trolling" question is discovered, the OP (especially if they're new here) should be directed to the Help Centre and the Tour so that they can either learn or be refreshed as to what's expected here vis a vis asking questions.
Kingledion already provides two possible actions above: downvote or answer the question. And there are situations where either might be appropriate.
But since this particular question is not on topic --- it's not about worldbuilding at all --- and is also trivial in nature & may be seen as an example of trolling behaviour, we're also within rights to exercise the third option which is to close the question.
The same logic that applies in this Q&A applies here, clearly. A trollish question is by definition also a trivial question, as it's more about riling up a community or seeking attention than it is about seeking advice about worldbuilding. This baby question is very much like the coffee question Michael Kjörling gives in his excellent answer to that question: a trivial question with an obvious answer.