Aside from practical issues, why make your datacenters so vulnerable?
The actual rack part is small, even if the solar panels and radiators are big. If this truly was super dangerous, ISS wouldn't be safe. And it's never hit mission-degrading issues due to micrometeoroids.
In any case, this is mostly for peacetime / civilian usage. Obviously military datacenters are and will be as secure as possible. Remember ARPANET was foundational for the internet.