The purpose is to share relevant content. Depending on where it was posted or how value-added the content was, it might get upvoted, ignored, or downvoted. Posting say crypto projects in Ecology will likely get nuked. Posting in crypto might get a solid up vote. Posting the same thing here might get neutral or mixed responses. Also, it is commentary that gets Rep and betting that gets Coins. 2 different processes. Click help here. Read the blogs. Read some of the top posts (rather than new) for additional info.
My personal metric is:
Is it spammy? If so, nuke.
Is it relevant? If so, upvote.
Is it neutral or mixed? Leave alone.
Is it porn or a scam? Block user.