For some, this is a feature. I need to keep my stuff out so everything gets at least a couple brain cycles every day. I work in a generalist shop though with many concurrent (and very different) projects so it's not for everyone. Never liked spreadsheets/ticketing systems for this. I keep separate files for each project but need to physically see the objects for it to work for my mind.

Part of the motivation is the minor discomfort of seeing so many projects open and set aside. For me the solution is to complete projects, not categorize and hide everything.