So far, I thought you will receive a penalty for duplicated content, but I ran into a MOZ article this week and actually it suggests the following:
You won't receive penalties from Google for the duplicated content, but it can affect your traffic, because Google may consider a duplication as the origin (for example if the site has a higher DA or more traffic) and in this case, this duplication will be shown in the search results as well. This would also mean that Google has an algorithm to choose the origin of non-handled duplications and 301 redirects or canonical URLs only help this algorithm to find the right source.
What do you think about this topic? If this is true, what kind of parameters should matter for this algorithm?
The article can be found here:
https://moz.com/learn/seo/duplicate-content
I suggest reading this as it was very useful for me -->
https://www.hobo-web.co.uk/duplicate-content-problems/
I hope this was of help.