My attention has repeatedly been drawn to serious negative effects created by the ability of Google and other searches to search and display pages outside the mainspace, including pages such as XfD's, DRV's, AN/I discussions, and the like. Some of these discussions have taken place on-wiki and others, I am advised, on discussion of OTRS tickets posted by affected persons.
Given the visibility of Wikipedia results on Google and other searches, and consistent with the overall intent of [[WP:BLP]] on En-Wiki (and what I hope is its equivalent on other projects), we have a serious responsibility to ensure that the overall effect of Wikipedia content is a responsible one. This includes eliminating the likelihood that the first hit on the Google search for a living person is not (for example) a deletion discussion on how insignificant and non-notable that individual is, or a page discussing the ban of that individual (who might be a minor, for example) who chose to edit Wikipedia under his or her real name and made some mistakes in doing so and was criticized or even banned as a result.
There has been discussion from time to time about implementing a technical modification such that only mainspace pages (or such other pages as the community might consciously choose) would be visible to searches. In view of the number of concerns raised about the current situation where everything is searchable, it seems to me that the necessary changes should be developed and implemented quickly.
The main argument in opposition to this change that I have seen is that the internal Wikipedia search capability is not as strong as the external search engines, so that it is desirable that the ability to conduct a complete external search be maintained. I know that I have sometimes found it useful to be able to search all spaces within the site in, for example, looking for precedent cases while drafting EnWiki arbitration decisions. It therefore would probably be desirable to upgrade our internal search capability. However, in view of the number of third parties affected by the current practice, I do not believe that implementation of the non-search capability should await this development.
As a matter of disclosure, although I have raised this concern in passing on prior occasions, my attention has been focused (this is something of an understatement) on it again by an ongoing and extremely unpleasant thread concerning me on the Wikipedia Review site. I understand that my concerns in this matter might be discounted for that reason. Nonetheless, they are sincere, of long standing, and I urge that they receive priority attention.
Newyorkbrad