@hfalcke
I grant that a 2 day embargo is pretty harmless to researchers. But the older funder OA policies permitted embargoes of 6-12 months, which is very different. The new policies are pushing back against that.
On your final point, embargoes are relevant to OA and open science because past funder OA policies permitted significant embargoes and now tend to prohibit them. In any case, I'm commenting on the policies, not trying to limit myself to any particular notion of open science.