Having trouble with SEO to target competitors' self framing

Hi everyone, I could use a bit of advice. I work in field A, and field B is related but positions themselves as equivalent, when they are not.

I've done a very long form researched blog post to explain why they are not equivalent (think Backlinko 'power page' style). But this post doesn't explicitly answer what people are searching for, nor target competitors' top keywords (which are in field B), so it's not ranking for much.

The post had to be done anyway, so I'm glad we did it. But we really want the message of the post to be visible for people searching in field B, and I'm trying to figure out how to do that.

Should I break up the long post into themes and rewrite those around specific keywords in field B? Rewrite the long post entirely to cater to field B keywords? Any ideas welcome.

Happy to provide more info by PM if necessary. Thanks in advance for any advice.