Hetzner Storage Box might fit you. Proper host, nice track record, hosted in Europe (probably matters, if you're not there, latency won't be great), unlimited traffic (as long as it's proper traffic) and cheap (no traffic cost nor setup).

- 1TB: 3.81 EUR (100USD cheaper than the DigitalOcean example you made)

- 5TB: 12.97 EUR

- 10TB: 24.75 EUR

- 20TB: 48.31 EUR

https://www.hetzner.com/storage/storage-box

I've been paying for two 5TBs boxes (+ rsync.net) for my backups for a very long time and had one issue one time when the connection to one of the boxes was degraded, but otherwise it's been painless.