I think it is reasonable, that they look for a responsible use of the money they get, to use cost effective Servers.
When the protocol works as intended, the owners of the servers will still not be able to easily link the users.
Discussion
Signal collects your metadata the same way that Whatsapp does.
All of Signals traffic runs across the Clouds of Google, Amazon, Microsoft & Cloudflare.
Here is explained how....
https://primal.net/e/note14hf9d3fkkhrsygkyzz8snuwyukckd4yqx0cq62z35cwp53a20a8suw457j
> Signal collects your metadata the same way that Whatsapp does.
Is this a claim you can proof?
The linked post explains that might server providers can link user interaction.
I did not yet read, that there are any other metadata collected than last IP a user logged in. From this no one could create a user network or with whom I am chatting.
This is what is known from court cases, where userdata from Signal was requested.