Although I agree with what you wrote, please consider these:
Paying bots for the promotion of your work is not ilegal or immoral. It's simple advertisement, which everyone does for more exposure. It doesn't reward effort, that is true, but it's not wrong either if some are willing to pay money for more exposure.
What haejin is doing is NOT about paying bots. He has an alt-account from which he games the system. He paid a lot for it to get so much voting power, that is true, and now cashes in on his investment by abusing this loophole in the system.
What is actually harmful is how his tactics are ruinning the credibility of the platform with literally worthless content at the top of the trends.
I personally never paid a cent for buying steem. I slowly get rewards by simply reposting my topics from elsewhere (which never got any monetary rewards there), so even if I get a cent, it's still more than I was making on the other platform. I am not losing something by not paying bots, and I am gaining something by being active.
What I am basically saying, is that Steemit is fine for sharing content and bots are not its biggest problem. Self votes are.
RE: Open letter to @Ranchorelaxo and @Haejin.