If Steem would be more like Reddit, that setup would work better. Sharing an interesting link would worth a lot because of the deep conversation. That's the only value that a link can bring, so it have to be rewarded. However, in the fear of plagiarism Steem has become more like Medium, tl;dr is rewarded more.
A comment that would want to compete with posts for the same reward pool should be insanely long.

Acts speak louder than words, many users apply minimum voting weight for comment, or not voting them at all. They show that those are worth less for them, even when they speak about the opposite.