Actually, upvotes do pay, it just takes a quite sucesfull post and a very early vote to get a payout (so far I once had one, of 0,001 steempower with 64SP, as n early voter on a trending post. So upvoting might not be the best way to get ahead here.
As to writing content. I see that you have written a number of posts which have gained 0,00$. We have all seen this, we have all had this You put in your heart and soul in a post, and it gets nothing.
I quicky learned not to care. I like the platform, and I like writing and commenting, and I will do just that, and if it throws a couple of bucks my way that's great, if it doesn't no harm done.
The trending posts make quite a lot of dollars, but even if you check out these writers posts, you will find that often the next post will get 0,12$ or so.