An example: a "office building" that has a large underground lab. Normal people see a construction site with a few dump trucks of dirt leaving. A spy will watch long enough to figure out it isn't just a few dump trucks, a lot more dirt is leaving than should be. A journalist has cover to watch long enough.
It is a double edge sword. A spy who can copy the real blueprints, or works in the lab is better. However the people who have that access to that might not talk at any price so you take what you can get.
The article is very clear about this being directed at journalists that are not suspect.
Why do you bring up this argument?
I mean, hit man could pose as doctors, I don't think you would argue that doctors should be patted down before going to work. Because the conflation is ridiculous.
This 'spies could become journalists' thing seems like a sophist government apologist point.
The whole thing is a farce designed from the beginning to be abused.
Then if one is especially suspicious one could put say 40k Americans on a list of suspicious people.
This is basically just saying none of us has any right to privacy which is the actual present case.
There's a long tradition of journalist/spies, already.