Just what type of logs do you expect Hetzner to keep?
Netflow data or equivalent? I'd assume any provider to have such records, at least in the short term. It can also be invaluable in debugging network problems post-hoc.
Splunk logs of traffic. It’s pretty common at the corporate level.
At minimum? In/outbound traffic
Cause that's probably just a TB of logs per short unit of time.
Not the traffic itself, just metadata (i.e. netflow).