How to check for keyword cannibalism

I have some pages on my site which I think might have an issue with keyword cannibalism. My idea was to simply put canonical from all the relevan pages to the most important one and see what happens.

Any experiences with this? How do you check if affected by keyword cannibalism?

I also need to know

no jokes, keyword cannibalism is serious af.

Whenever I need to check for and fix keyword cannibalism I go back to this Matt Diggity article: https://diggitymarketing.com/keyword-cannibalization/

Simply list those pages in a speadsheet and the keywords associated with them. Now check whether the pages are clone of one another in terms of search intent and main topic in it, even though they have unique content. If you think they are same, combine them into a single master page for each topic and 301 redirect the removed pages to the single master page created.