Extend the x and y axis?
> How would this justify its cost?
Presumably by saving costs elsewhere? Labor, chemical inputs. Not saying it's there yet though, but why should it be?
> How does it withstand being outside all year, year round?
A cursory glance at the specs indicates that they've considered waterproofing at least. I imagine "the elements" will prove even more challenging than expected, but it's not like this wasn't considered.
> How does it not just destroy your crops when they grow tall?
The y axis is up pretty tall, and the manipulator is pretty narrow to get down in between plants. Clearly it is not advisable to grow crops that are taller than will fit in the machine.
> How could this possibly improve on current farming methods
Automation? We don't expect Burger King robots to improve on culinary techniques. I feel this is mostly interesting for repeatable research uses, but as basic manual labor savings it's interesting as well.
(I am in no way affiliated with this project... just seems easy to see the potential, and odd to treat a prototype as if it needs to make a business case right out of the gate)