For this route to be done optimally you have to jump on a specific frame, but even if you don't do it optimally you still need a frame perfect teleport to survive, which sucks a lot.
Not only that, but the end is also way harder now, if you get there at the same time as the TAS, it requires a frame perfect jump plus a frame perfect fireball, if you get there just some frames behind the TAS, everything up to 6 frames slower than it REQUIRES a very precise double jump and a frame perfect fireball throw.
With all of this in mind, the best possible time for a human now is probably 4.75, but if someone has the balls to go for a very precise and quick double jump to a frame perfect fireball throw after a good enough run to be less than 7 frames away from perfection, a time under that could happen, and if someone grinds enough, a 4.6X might happen some day, only time will tell how low this time will go.