An important part of this, is that the affordable housing requirements in Downtown / SLU are so low, in some areas as little as 2% of the units would be required to be affordable.  

https://outsidecityhall.wordpress.com/2017/04/13/even-raging-grannies-cant-convince-council-to-do-the-right-thing-in-downtownsouth-lake-union-rezone/

Johnson's justification for allowing the richest of developers to contribute the least, was that the low requirements would encourage already permitted projects to opt in.  Then he gave a misleading press release, when the reality is much less impressive.  But we are still stuck with this legislation that is a total corporate giveaway to richest developers while pushing the burden onto everyone else.

Thanks to George Howland and Councilmember Lisa Herbold for exposing this and to Seattle Weekly for sharing this story.