It would be far harder and more expensive to reuse parts.
Just because there are mechanical parts and doesn't mean that they are reusable or serviceable.
Humans have basically no ability to do any manufacturing construction or service in space. It takes an 8 Hour Eva to change a couple bolts, risking human life all the time.
Bringing all of the tools and equipment to space to facilitate reuse would require far more than simply replacing it.
On top of that, most of the space station is worn out and far beyond it's design lifetime.
Further away than non-space robot workers, and we don't really have those either (at least not in the sense of machines operating autonomously in arbitrarily complex environments such that humans aren't required at all)
Just because there are mechanical parts and doesn't mean that they are reusable or serviceable.
Humans have basically no ability to do any manufacturing construction or service in space. It takes an 8 Hour Eva to change a couple bolts, risking human life all the time.
Bringing all of the tools and equipment to space to facilitate reuse would require far more than simply replacing it.
On top of that, most of the space station is worn out and far beyond it's design lifetime.