I will continue not to use bots,

That's alright. I don't judge anybody, whether he uses those services or not. It's your decision, after all.

because I think the little more visibility does not really change anything.

But I do disagree in this case. I can see the impact of paid upvotes. It pushes every important aspect of your blog: visibility, followers and interaction.
@spiritualmax put it quite nicely in this article.

and I had trending posts in science and health tags without bots not so long ago - that is entirely possible without bots, even for quite fresh users - in part thanks to steemstem/curie.

I had this luxury too. But not only in part, but solely thanks to the appreciation of steemstem/curie. But this is a luxury. I am always happy about it, but I can't rely on this. With paid votes, I don't have to hope so much for the generosity of the community support.

And this way, I do not support this crazy system, but I rather push for a change wherever possible (for what that's worth).

Sure, I absolutely agree. I would like to live in an ideal world where amazing content gets the attention it deserves, too. But that's not the case and it may never be.

You are of course entitled to your own opinion on this. But please, start waiting a little more than just 30 min to kick in the bot. Your curators are humans too. Give us time to react to content.

This whole discussion made me think a lot. Most likely, I will either refrain from using bots for steemstem stuff (at least the posts, which are probably going to be rewarded) or wait until after the vote, so you guys can still get the whole curation reward out of it. I think, that's a reasonable way of dealing with this issue.