Why have so many people missed why David Grusch said disclosure was originally taking place?

In his original article for Debrief Grusch said the reason for disclosure was because:

“It was dangerous for this “eighty-year arms race” to continue in secrecy because it “further inhibits the world populace to be prepared for an unexpected, non-human intelligence contact scenario.”

So he must be aware (and others in his position) of the possibility of an “unexpected non-human intelligence contact scenario “

https://thedebrief.org/intelligence-officials-say-u-s-has-retrieved-non-human-craft/