Doing it 1-2 days/week is the difference between being able to get some focus time to deliver something of value, and just being an internal search engine.

My job has lots and lots of calls. I am happy to leave most of my calendar open. But most mornings, and at least one full day every 2 weeks is mine, and no, you can't have it, you're not entitled to it, it's important to me I have that time to actually do focus work.