There are definitely good reasons to, at minimum, have you _available_ from 9-6; say, for a meeting or to bring a coworker up to speed on what you're working on, but at the same time you don't necessarily need to be pinned to your desktop for the entire period of time to do that. Since remote working started I've taken advantage of that big time by just running errands during the work day but keeping my phone close by in case I get a ping on Slack.