> There is an exception in the DMCA for abandonware
Those sources indicate the DMCA exemption is only for single player games requiring online activation where the server is no longer available. That is probably a tiny subset of "abandoned" DOS games.
“I'm not a lawyer or an expert, but looking at the Wikipedia page for the DMCA [0] there appears to be protection for retro games:
An exemption was made for 'Computer programs and video games distributed in formats that have become obsolete and which require the original media or hardware as a condition of access.'
EDIT: Actually archive.org posted an article about exactly this [1]”
See the link for citations. My understanding is that there are a combination of factors that coincide to provide a safe harbor for the Internet Archive to serve this content.
Those sources indicate the DMCA exemption is only for single player games requiring online activation where the server is no longer available. That is probably a tiny subset of "abandoned" DOS games.