Sure, depending on the specific conditions at that area. (I've seen plenty of spots, over the years, where it's simply impossible short of a serious out-of-the-way jaunt [of hundreds of yards, if not a good mile] to avoid a certain spot. In this instance, the guy was going down a legitimate "slow" lane with parked cars on one side and a barrier on the other. At that spot, he was there, not unlawfully, and faster-moving overtaking users of that path have no authority to simply mow them down and shove them aside ... which is, basically, what the guy was doing in that person's case. (Explaining the guy shoving back forcefully, once the bike was essentially shoving its tire up his backside.)

Where there are alternative choices, as you say, folks shouldn't be there. Though, that still doesn't give people authority to force people off the lane.