In the beginning of the video below the player says: "Okay, good, it doesn't look like I lost anything with that crash."
https://www.youtube.com/watch?v=bWyvjyOiMAI
Which makes me think the issue is random crashing and data loss.
This game may indeed be "speedrun proof" because nobody can finish a run without runkiller crashes.
But I think it is not "TAS proof" because TAS player can avoid crashes by playing differently. That is, if you can set it up.
I think the game may be nearly TAS proof because even if you can avoid crashes it is a big demotivator to retry random solutions just to avoid arbitrary crash. As for the game itself, it is difficult to find good random seed for procedural city generation because you do not know the long game without testing different setups. The game may not be "absolutely TAS proof" but just very very hard, which is practically the same thing, and the reason why I hope somebody will try to TAS it! :-D