EDIT -
As I stated in the comments, IMHO the policy banning these kinds of questions is not good long term. Apparently this is relatively new policy.
The primary objections are just as true for other questions, and problem questions or answers can be handled just as they are for any other question. This issue was why "community wiki" was first established, and I think "community wiki" dealt with it fairly.
- If the question is not generating good discussion, then close it as unconstructive.
- If the question is question is generating answers that won't last, close it as too localized or edit it to make it more general.
- If it is duplicate, close it as duplicate.
- If an answer is just an Amazon link, downvote with a comment requesting explanation.
- If an answer describes multiple items, with different attributes and reason the items are good, upvote it.
- If a comment is arrognat or insulting flag it.
- If the issue is one of reputation, then put limits on how much rep one can get from a single question. Or do so for questions with "off topic" or "list" or "subjective" tags.
I think I have made my point.
Beofett closed the "Best Book" question.
I disagree. Many of the SE sites have one (or several) Best Book question, and they uniformly provide great info.
Server Fault - 46 upvotes, 3400 views
Stack Overflow
- JavaScript - 122 upvotes, 60 upvotes for the accepted answer, 19,600 views
- PHP - 95 upvotes, 3 answers with > 10 upvotes, 42000 views
Programmers
- Java - 7700 views, 195 upvotes, 318 upvotes for the accepted answer
Bicycles - Maintenance - 12 upvotes, 250 views
The policy about avoiding "no right answer" questions is generally sound, but is applied pedantically in this case. The "best books" question is going to improve the site, not detract from it.