If you are gonna go for TrueNAS, try Storj with TrueNAS Cloud task. TrueNAS made a partnership with Storj and the price is very good. www.truenas.com/truecloud-backup/

TlDr; The data is encrypted with restic and sent to Storj S3 storage that is further fragmenting it (and encrypting it too - so double encryption) into multiple pieces (with redundancy) and storing on other peoples TrueNASes (you can also provide your unused space btw and gain some small money back).

I am in process of setting this up (already run a working test backup) and I didn’t find anything that’s better than this integrated solution. Very cool!