I might be an unusual case, but when I present graphs/charts it's not usually because I'm trying to point something out. It's usually a "here's some data, what conclusions do you draw from this?" and hopefully a discussion will follow. Example from recently: "Here is a recent survey of adults in the US and their religious identification, church attendance levels, self-reported "spirituality" level, etc. What do you think is happening?"
Would love to hear a good example of alt text for something like that where the data isn't necessarily clear and I also don't want to do any interpreting of the data lest I influence the person's opinion.
An image is the wrong way to convey something like that to a blind person. As written in one of my other comments, give the data in a table format or a custom widget that could be explored.
> and hopefully a discussion will follow.
Yeah, I think I misunderstood the context. I understood/assumed it to be for an article/post you're writing, where you have something you want to say in general/some point of what you're writing. But based on what you wrote now, it seems to be more about how to caption an image you're sending to a blind person in a conversation/discussion of some sort.
I guess at that point it'd be easier for them if you just share the data itself, rather than anything generated by the data, especially if there is nothing you want to point out.