Your opinion is valid, maybe if you'd vote for a post on a quality measurement and not a quantity measurement this could solve it.
"Excellent, Great, Average, under average, poor". (Or a similar well thought scale). And the rewards would be calculated after the 7 days following the grades of the post.
Its not even about quantity if a content is good and has value. But if you upvote post or comment that only says "hi steemit" and you earn money thats just stupid and people will abuse the fact
Quality measurement would require quality people to measure it.