Users bumping up questions that are years old just to get in an answer or comment?

Question

This post has an answer and 72 up votes, 15k views and is 2 years old bumped up with an answer by SEO

https://webmasters.stackexchange.com/a/27196/10527

Another post in the meta Are you going on marking community wiki each SEO question?

And someone says You are commenting on a question which hasn't been active in over a year

Are there guidelines for this? Isn't this a step up from people commenting saying "Thank you" If it's an old question and no answer or selected answer I think it's fine to dig up old questions but ones with a clear answer like that?

Answer 1

Are there guidelines for this?

This behavior is allowed and even encouraged because it can be useful - particularly in cases where the accepted answer no longer reflects the best solution.

If you find that the material that is added is not relevant to the question, use your best judgment and simply ignore it or downvote with a comment if you believe that doing so will encourage the answerer to reconsider the post.