Neither wine nor xterm have virtualized cpu or memory, they both imitate (= emulate) some system via their interfaces, yet one is primarily an emulator and the other is not one. That does not make sense.
The wine project changed name to avoid the bad reputation emulators had back then due to their poor performance. "Wine is not an emulator" is not factually accurate, its a social workaround.
Words can have different meanings in different contexts. "Wine is not an emulator" was a very useful tagline to indicate that it was fast, as opposed to virtual machines like Virtual PC, PCTask etc.
The wine project changed name to avoid the bad reputation emulators had back then due to their poor performance. "Wine is not an emulator" is not factually accurate, its a social workaround.