Hello @chris_adams ...
I am sorry to see that your question has been sitting here unanswered for over a month. While I don't exactly have an answer for you (I have no experience with Moodle), I thought I'd check in with you to see if you've been able to come up with any solutions on your own since you first posted this question. If you have, would you be willing to share back here with the Canvas Community? Or, if you are still looking for assistance with this, please post a message below. I will go ahead and share your question with the https://community.canvaslms.com/groups/lms-migration group here in the Canvas Community in hopes that it will gain some additional exposure. If you're not yet following that group, please click on the link I've provided, and then click on the "Follow" button on the top right corner of the page. I hope this will help, Chris. Good luck, and looking forward to hearing from you!
Sadly the import function doesn't convert Moodle forums to forums in Canvas. I've got a lot of resources in Moodle forums from 2015/16.
I've had a another look at the Canvas discussion tool and they're not very good. Or at least they don't work like conventional Forums.
I'm not alone in the criticism of this tool:
Hello @chris_adams ...
I thought I would check in with you again because there hasn't been any new activity in this discussion topic since April 12th. I hear you on converting content from one LMS to another. A few years ago when we made the switch from Pearson eCollege's LearningStudio LMS to Canvas, we also ran into a couple issues. One of them was that graded assignments in LearningStudio came over as standard "Pages" in Canvas and not "Assignments" that could be graded in the Gradebook. So, my team had to spend many, many hours checking over our courses and manually converting each assignment to use the toolset that Canvas offered. As I stated in my first response to you, I don't have any experience with Moodle, so I won't be able to answer your question directly. But, since there hasn't been any new activity in this thread for quite a while, I am going to mark it as "Assumed Answered". That won't prevent you or others from posting additional replies below, however. I hope that's okay with you. Looking forward to hearing from you, Chris.