Why should monogamy be considered the default?
Because it is usually part of the marriage vows. If it is not, then the idea is fuzzy unless discussed in advance.

If I don’t trust myself to ask for what I need/want, then how can you trust I won’t be angry or hurt about things which maybe seemingly inconsequential to you?
This may be one of the least obvious, but most perceptive, statement in the entire article.

I will probably spend a few days thinking about this.

I just added a link to this article to my article on values: