Yep, I think it was somewhat of a failsafe measure, as people also tend not to use or respond well to the downvotes. As for Spam, looking at YouTube and Instagram etc, they don't seem to mind it, which means that the users are used to ignoring it - kind of like banner ads on the sides of articles.

On the tokenized interfaces, dealing with it all is easier as they are centralized. The problem is in the decentralized greater environment, people don't like the idea of downvotes and blacklists.