That is complete bullshit. They not only don't need to board but if they pulled a gun the TSAs would be an unwitting accomplice in letting them reinact "No Russian" with their bullshit security theater gathering hundreds into a massive shooting gallery with no cover. Really that is why there was such outrage over the level - it illustrated vividly how the TSA failed on the most basic logical level.
This actually came up after the 2015 attacks in France. Most crowded locations became heavily protected, bags were all checked, etc. The result: a massive crowd in front of theaters, concert and sport venues, etc. Israeli consultants basically summed it up by saying that these procedures were creating massively vulnerable areas with potentially 100+ victims if a guy detonated a bomb in front of the venue.
I remember seeing a documentary showing how in Israeli airport one of the main goals was to always avoid long lines and big groups of people.
Context: "a controversial level in the 2009 video game Call of Duty: Modern Warfare 2. In the level, the player can participate in a mass shooting at a Russian airport.".
