I only used life a few times in 4 months here, if you have data to show otherwise, I'm interested. It seems to be a generic tag for when people don't know which tags to use. again, that's my opinion. Seeing that a post has the tag #life gives me 0 information about what the post actually relates to without the title first lines and the rest.
If it was more specifically explained what the tag is about and what should be used for, it could be a useful tag, imo. Otherwise, everything under the sun is life.
RE: Steemfest: An analysis of the tags used by Steemfest attendees