1. Nostalgic appreciation for historic UI designs > "I love this kind of thing :)" – lynndotpy
2. Critique of modern UI trends and loss of usability
"This feels like the result of a competition to design the worst possible user interface. To about 5% of people it might be an accessibility feature, to everyone else it's worse, and people with beards, marks, or dark‑skinned faces are going to find it a disaster." – adrianwaj
3. Focus on specific retro systems and resources
"IRIX 5 was so clean!" – keyle
4. Desire for substantive UI innovation / missing improvements
"Can anyone name a single substantive UI improvement in the last 20 years?" – washingupliquid
5. Archival concerns and legal/ethical issues
"Unfortunately they haven't released them yet, because of the unknown copyright situation." – mananaysiempre