Interesting. I'm pretty sure it's there to make sure you don't unfairly miss getting the trinket. Think about it: you free the moving platform from above, and then kill yourself. But the platform is on the left side of its movement path, and is now stuck and unusable! Oh noes! So the moving platform is teleported to the right so that you can use it to get the trinket no matter what. How unlike the person who created Doing Things The Hard Way.
In that video, the moving platform is actually teleported into the gap, and common sense would say that it's free to move. However, it's a custom coded event, so it won't move unless the disappearing platform is stepped on. That's also why there's no checkpoint in Exhaust Chute.
