It's a management cop-out to push this narrative though. You've destroyed your efficiency, you make guests wait hours for something that is unnecessary, you keep charging more, and giving people less for their money - and is a complete fallacy.
A courageous person would be confident to stand in front of the Coroner and testify that even though the incident happened at X point in the ride, nothing the supervisor could have done would have changed the outcome until the train reached the brake run. (Let's not forget that the ride time is just over a minute and almost half of that is the lift hill).
If that isn't good enough, or you want to go further than that, install additional E-stop mushrooms along the station wall so the operator can reach it from any position on the station - or a pull-cable strung down the length of the station like they do on quarry conveyors so you can pull it no matter where you are along the length.
This is the problem with people doing risk assessments with only the direct cost in mind. Someone did a risk assessment on TRRR and concluded that many safety upgrades were needed - but due to cost, they decided not to do them all straight away and went with what they felt was the most important features first (they were wrong). A lot of the TRRR safety measures that had been implemented were administrative controls - and keeping the supervisor at the panel - when it is clear that first, it makes no difference and second, it hurts your guest experience - when for a little extra cost you could upgrade the attraction to eliminate the issue, is pathetic.
If you're going to knee jerk your way into tanking your capacity, then spend the money on additional labour so the supervisor can stay at the panel, AND you have another station attendant to check harnesses to keep the trains moving.