The trouble with a completely random hostname (or username---mine is pc2g4d after all) is that they're used by few enough people, and when sufficiently long are

The trouble with a completely random hostname (or username---mine is pc2g4d after all) is that they're used by few enough people, and when sufficiently long are easily distinguished from non-random strings, that maybe they can actually reduce anonymity. For example, if you see the following pool of usernames: alice bob charlie W2zwAe3W9oVkRK9aSXWnTsxLj And then in another context you see another pool of identifiers: doug erin filipa iA4PrG7jtp6hmNQNVDCqk36C Which of these don't belong? It seems at least possible that the random identifiers were generated by the same person, or at least the same type of person. The fact that an identifier provides no information is itself information. I wouldn't be surprised if this could be a useful signal for linking accounts that are meant to remain totally unlinked. So totally random MAC addresses or hostnames could just cause you to stand out.