Tape is valuable when you want true off-line backup, that's not connected to a system or powered on at all. Yes, you can do cold backups on hard drives, but they're more likely to fail when restarted after 6 months or longer.
Even in the External Links section? How annoying. Were these general MUD Wikis, or ones specific to a single MUD?
The thing is, if you want, you can setup MUDWiki that has all of this data for all of the great MUDs going back into time. Once you have that site, you can add it as a prominent link on the Wikipedia MUD page. Wikipedia doesn't have to contain every piece of information itself.