Earlier quoted context omitted.
Totally, but that's what syndication is all about. The best is to have the original content on your own blog and then to cross post it to Medium, with the canonical link linking back to your blog. That way, if/when Medium is replaced by another platform, you don't loose your content and your have already build some SEO for your blog.
I've heard that Google deranks content it believes to have been duplicated, and I don't know if that's really true but I've been paranoid about copying my existing Medium content to my new blog; if it's true then Google will certainly give precedence to Medium.
From the source: https://www.youtube.com/watch?v=mQZY7EmjbMA