Their fact checking is completely useless. They don't check any of the most important or fundamental claims, only the very trivial. Editors apparently don't care or are incompetent.
In the case I'm intimately familiar with the reporter made no claim or attempt at impartiality. He was actively hostile and came close to threatening. He was on a witch hunt and continued his vendetta over a couple years of trumped up articles until he realized no one else bought his bullshit.
I pray for the day when shitty journalists can't hide under the umbrella of a "respected" brand like Vanity Fair. It's too much power with no effective checks or balances.