A satellite is already a collection of multiple servers in different locations. So if one server burns down you wouldn’t even notice it. Let’s say for some reason they all burn down at the same time. Your data would still be stored in the network and can be recovered as soon as the satellite gets back online. One day we might also implement a migrate or copy to another satellite.
The segment fee is in place to make small files expensive. Ideally you store big files. Some great tools to manage that are Duplicati or Restic. They will combine many small files into a zip archive. I wouldn’t worry too much about it. The free tier coupon should cover most of the costs anyway.
As far as I know wasabi also has some hidden fees. It is hard to tell which one is actually cheaper.