If we upvote an individual for one photo and a few sentences, an individual who’s only contribution to the ecosystem is that photo..

That was the way this sounded, but if it's not what you meant that's on me.

...but the reward pool is set up to reward contributions to the ecosystem. If we are not using it on the things that add long term value, we are wasting it.

I don't really agree with this. If we assume code is law, the reward pool is set up for individuals to reward whatever they want. The reward pool setup is totally agnostic. I think that's a strength not a weakness. As individuals we can use our stake to add value to the platform in whatever ways we see fit. It's going to vary drastically from person to person, group to group.

Truth be told, in regard to artist friends leaving, it was a variety of factors, and what I mentioned above was one variable. Rewards were actually not much of a factor. Artists are used to posting their art and being paid nothing. It was actually the lack of engagement, so I definitely agree with you that this is key and super important.