Setting rel=canonical to home page is absolutely terrible for SEO, right?

I'm looking into a website and trying to ascertain why its performance is not as good as would be expected. I've noticed that every page has the canonical URL set to the home page. This should hurt SERP rankings significantly, right?

Someone who has dealt with this before, insight would be appreciated. I'm almost certain this is at least not optimal, and it would seem that this would be incredibly harmful.