>>123863
what's the use case?

XP is smaller and supports older shit better.
7 still runs loads of modern software (it is dwindling by the day though as shit starts to require 10 and up).
Both are insecure due to age, XP much more by default due to choices it made for legacy support, although you're also less likely to get malware that actually runs on XP due to age (it is still a threat - you'd need like Windows 98 to age yourself out of threats like that).