That is ridiculous. If the vehicle in front of you is traveling 75mph and you want to travel 80mph, it is not impossible for you to drive safely. If the vehicle in front of you seems especially dangerous to be behind, it is still not impossible to drive safely.
I recently got run out of my lane by a semi who swerved in from the left right on top of me in the far right lane. The semi then kept swerving from the right shoulder to the left shoulder erratically. The driver was obviously extremely impaired and re-passing was risky. But it did not make it impossible for me to drive safely.
I drive a two-lane highway everyday that has no reasonable alternate route. The posted speed limit is 55mph. It has double yellow lines along much of its length. I frequently get stuck behind somebody poking along at 45mph or slower. I fully understand how frustrating it is. But that doesn't mean I can't drive safely.