I think the reason that so many of the orphans are technology related is that they are often very specific, which makes them difficult to answer. The more general they are, the more likely they are to be answered.
To answer the second part of your question; no, the mods will not delete them. In fact, leaving them as Orphans is helpful, because they can easily be sorted by clicking on the Orphans tab, and users can then browse through them and (hopefully) answer some of them. That’s why giving off-topic answers to Orphan questions is really unhelpful, because they’ll lose their Orphan status, and won’t be as easily sorted and found by someone who potentially has the right answer.