I also used to download absolutely everything. Now I need a free afternoon (or three) to sit and go through all my files and purge them. I like the idea of "if I wouldn't pay for it, don't download it", but sometimes something just catches my eye and my imagination, and I download it even when I am pretty sure I won't ever use it.
I pick and choose what I want to download. And I don't always unzip what I download if I know it's for a later project. I've gone through and either zipped and archived things I haven't used but want to use or use again. I also culled out and deleted items and kits that don't interest me now.
As almost everyone else has already said, my tastes are evolving. I"m no longer the new baby graphics-vampire that I was. I don't need every kit, template, action, script or item that I see. I know more, so I can be more discerning on which freebies I download or items I purchase.
And the designers are growing, and learning new techniques or expanding on existing ones. I know that I'm very sheepish when I look back at some of the things I designed or put together a few years or even a few months ago. I've learned so much since then!