I'm not an expert either and maybe not the ideal socialist to answer your question, but I think people will need to ask themselves, do I need to benefit/profit from this perpetually, or will it be more beneficial to have my work be part of the common good? I think individuals of sound mind will be fine with allowing their work to go to charitable use, just as old furniture and items often are donated for good causes after a long time. The fact that they get something from your work doesn't necessarily mean a bad thing for you, but sometimes capitalistic tendencies want to profit from your benefit while harming others, such as an artist's estate starting frivolous lawsuits when the artist would never think to do such a thing.
In the copyleft sphere as it exist in today's society, almost all licenses say that creators should assert their intellectual property right in order to allow for free and libre development/improvement, and discourage and dispel corporate fuckery.