There was a time in the early 2000s when Firefox triggered a browser renascence and there was a lot of excitement about what a "browser" could be...feeds, blogging integration, collective tagging, open comments....
The original spirit that the web should be as writable as it was readable, extended to shareable.
And in some way, shaped by economics and technology, we got an approximation of that vision..shrinkwraped and sanitized.