Could be done with a moderate-spec single server. Replace the JBOD enclosures with on-server 8xSamsung EVOs in hardware RAID6, and gain a bit in speed because we don't have drives that slow anymore. Xeon E5v4 could replace the computational power. Network multihoming would be done the same, except with 10000baseT instead of multiple cables. Run nginx on it and you're good.

Or, one could host the entire thing on S3 with CloudFront at a fraction of the cost.