It takes effort to comment on Reddit. But not that much effort. It takes effort to find cool sub-Reddits that appeal to you. But not that much effort.
A little while ago, they had a thing called "Front Page" or something like that which was basically Reddit curated content without the Reddit features such as submitting, commenting, etc. I don't know how that turned out, but seeing as how I never see it mentioned anywhere, I don't think it was that successful. Makes me wonder if this redesign will have a similar impact, that is, near none.