Before answering your question, we would like to clarify that in this case we are referring to server-side encryption, not end-to-end encryption.
And now the answer. No, encryption of the files you will use in our instances is not enabled. The reason is that encryption involves a number of technical difficulties in managing the instance. If this is a requirement in your case, please contact us and we will consider enabling encryption in your instance.
However, we emphasise that one of the main reasons for enabling server-side encryption, i.e. using a third-party provider for Nextcloud primary storage, does not apply in our case because RCA Systems is the exclusive owner or operator of all storage systems involved in the service.