Given we are just about to start our first tests with indexing article placeholders (see T144592), we need to decide what to do with the placeholders that are not notable.
We could make them:
- noindex, nofollow (=> don't index and don't follow links)
- noindex, follow (=> don't index, but follow links)
- index, follow
No. 1 would lose us quite some links to other pages (and maybe later on also other placeholders) from these placeholders, but we would also potentially save us from some requests (not sure how often search engines pokes such pages). There might also be negative side effects for other placeholders that are indexable (depending on how search engines treat these things).
No. 2 wouldn't save us any traffic (probably), but it would still give our links at least some weight (potentially, no idea how search engines actually rate these).
No. 3 would lead to empty and almost empty placeholders to show up in search results, that's probably a show stopper.