While reading this I kept thinking of my experiences at work with asking people to review documents. The ten or fifteen times of "Looks good" "Nice job" or similar one liners, it became obvious they weren't reading the documents or even looking at them. Unfortunately that manifested itself as things began to role into an implementation phase.
The same can be said for Steemit. Most great things posted have no comments or comments that have no critical feedback, advise or critiques.
It takes a minute to write something insightful or helpful, but even that seems like a hurdle for some of the one liner folk. Live and let live, I guess.
My personal method would be to leave a comment to the tune of 'for bookmarking purposes, will read later' if I didn't have time to analyze a post, rather than a one liner like you mentioned above.