Costs and Logistics
Anyone can make a digital compilation and “distribute” it to millions (see above playlist). Creating CDs, however, has a much higher cost, and they still need to be distributed.
How are you going to do that? Offer them on eBay and hope someone buys them? Or offer them for free, then package and ship them (also for free), because no one would be willing to pay for home-burnt CDs with pirated music?
I think these make more sense as playlists in ListenBrainz