Transhumanist and Marxist?
Well, it's not "woo" in idea. We will some day understand exactly how we make memories, and therefore exactly how to replicate them. At that point we will be able to map all the memories and thoughts you've ever had and recreate them.
I don't see how 'uploading' someone's memories would be impossible. Of course you can't 'upload' 'all of a person', as a person is also their body, but memories and personality and stuff, yeah, that seems pretty plausible.