As far as I know, there are bins for that in a lot of places as well as just calling Salvation Army and other existing groups. Solution for problem that does not exist.
Yup - that's my reading of the situation as well. I'm moving to London in a few weeks so have been cleaning house for months. Both my beautiful wife and I have rounded up a LOT of clothes in good condition that aren't useful to us anymore - these were put into bags, and I did multiple runs to nearby charity bin at a time when the motivation struck me. Five minutes from thought to being rid of the clothes.
It was easy as pie to do so, and those clothes will be sold for cents on the dollar to people who need them who can go to any number of thrift stores and take immediate possession. Easy browsing, no shipping costs or time or web access to consider.
Good to see someone chasing charitable projects online. This one doesn't strike me as being practical, but perhaps the next idea will be.