Sure, but is that how we talk about our institutions? Things I hear that buck anarchism while supporting American democracy:

• The Constitution should be interpreted with "originalism" or at the very least venerated
• Police sacrifice X, therefore it's okay if they do extralegal Y

I'm not saying there aren't systems of accountability that legitimize various institutions. It's that the stories we tell to legitimize an institution comes in many different flavors, and those based on authority from power/position (ie "our founding fathers were smart people") are not accepted by anarchists. Edit: Imagine how different our legal framework would be if it reflected that mentality?