Example: User "Samir Patel"'s first question as a new user today. Deleted as it should have been since it was attached as an answer to another question, however it would have made a very answerable question if published as one. Since it is not commentable, and there is no private messaging (thankfully, most of the time), how to help such questions find their own spot, instead of it all ending with a newbie leaving frustrated? Reformatting and reposting the question as me would be clearly robbing the original poster. Commenting the main question would be out of place too AND be very confusing to non-moderator-tools users.
There's absolutely nothing wrong with reposting, if you feel you understand the question well enough to make it clear. It's not great if people are likely to need to ask for further details and clarification, since you may not actually know how to respond. This is definitely not "robbing". If you put in the time to write a clear question, and post it as a question, you deserve the handful of upvotes and the reputation that comes with them.
The answer you mention... well, it looks a wee bit broad and vague, so I wouldn't want to adopt it myself, but if you think you can, go for it.
We mods do generally comment before deleting, though sometimes we don't have time, or figure it's not worth it if the answer is very far from a reasonable post. (I wasn't the one who deleted that specific answer, so I can't speak to why it doesn't have a comment.) Note that anyone can comment, e.g. when flagging for our attention, so you don't have to entirely rely on us. That said, honestly, it's very rare that a user actually heeds the comment and posts their question as a question.
Beyond adopting a question, or commenting on the answer before it's deleted, there's not really much else we can do within the framework of the site.