I think it's smart to keep that kind of language out of the conversation at this point.
There's no reason to freak people out until we have eliminated Russia, China, and the U.S.
However, as Sherlock Holmes said, "When you have eliminated the impossible, whatever remains, however improbable, must be the truth." Some Navy pilots have already said that, in their opinions, it isn't ours and it isn't Chinese or Russian. It's been around since at least 2004 and, in 15+ years since, that kind of technology (or some offshoot of it) would have been noticed despite efforts to keep it secret.
Even if it goes unsaid, a lot of folks (even at the Pentagon) are still thinking about the possibility of intelligent non-human life of some kind. So it's in the conversation...just unspoken.
If it was the Chinese, they would have had a leap in tech by 500 years. I highly doubt that. How could they go from sucking all our tech one minute to surpassing us by that amount?