If you're out on a trail, where your environment is the trail, and your compadres are your compadres, sure talk to them. You have shared goals, your adversity comes from the non-sentient or sub-human sentient environment. Truth is clarity, clarity is action, action is goal.
But then you're not out on a trail, your environment is other people, and your compadres are transient. You need to have a public face, a policy for your sentient environment. And you want to save the truth and clarity for when you have a thing to do with someone that shares your goals. Obfuscation leads to non-interference, leads to less adversity, smoother action, closer goal.
There are many levels and gradations to this. Push it too hard for the situation at hand, and you get confusion that leads to demoralization, and mass hysteria that drives harmful public policy.
First we farm the land, then we domesticate the animals, then we govern the people. The toolkit is the same toolkit.
At any given time some people are your land, some are your animals, and some are your compadres or adversaries. You don't owe any truth to your enemy, nor your sentient environment.
This is indeed very difficult if you're high in openness, but that's how it was before you got here and it keeps on rolling like that. There was no reason it should change, so it didn't.
It's not like deception came into disuse at any point. Lying is what it is, human. Part of the way communities work, and social dynamics develop.
What was the point of the article? Acceptance?
That's an individual thing. A situational thing. You shouldn't just roll with deception, but you should expect it everywhere.