How to think about paper acknowledgments?

In our most recent "how can we help you?" thread, a reader asks:

I am an early career researcher working within the history of philosophy. I am about to write the acknowledgements of a paper that I recently got accepted for publication.

My question is: After having presented the paper twice at the beginning of my phd studies, I ended up changing the thesis of the paper. The interpretative issue that I discuss is still the same, but the solution I propose is completely different. How should I deal with this when writing the acknowledgements?

Needless to say, I will thank everyone who has read previous versions of the paper. But it seems odd listing conferences where the audience have heard me argue for another interpretation. Is it better to leave out any mention of the two conferences? Or should I include them and potentially comment upon this change?

We've never had a discussion of how to acknowledge people before, so this is nice opportunity to examine the issue. Who should one acknowledge in a paper, and why?

I think the simple answer here is: one should acknowledge any people (including audiences) you can recall who heard or read any version of the paper who might have influenced your thinking leading to the final product. In this case, even though the OP changed their thesis, it seems to me entirely plausible that they might have changed their thesis in part because of feedback from audiences who heard the earlier version of the paper. So, in this case, I would absolutely thank them. I also don't think it's necessary to go into any more detail than this, such as commenting on how one's thesis changed over time. Of course, you can say something to that effect if you want. But, in the grand scheme of things, acknowledgments are a rather small thing, and I doubt there's much need to mention these details. I mean, don't get me wrong: it's important to acknowledge people. My point here is that nobody reading the paper (including people who attended talks where one gave earlier versions of the paper) is probably going to care about these details. At the end of the day, the primary focus is going to be on your actual paper! 

But these are just my thoughts. What are yours?