... i always find it interesting promoting S3 as a Backup Storage for Disaster Recovery. From my point it is mostly a "no, no and no", even if i have not seen it working.
BUT what i have seen multible Times is a Ransomware attack. And if you are in such a Situation, i am sure you will have no Internet Access, as this is the first which is "plugged out" ....
but hey, the local Datacenters MUST have the same limited tech which is used in the Internet . ( i mean an S3 could never ever match a SAS/SAN Storage / Tapes in Speed and costs ) ....
Everthing which has admin rights could be hacked and deleted,factory reseted ( HW Servers, OS , Storage ) , but NOT Tape . This could "only" be erased in sequence ( very slow ) or physical destroyed , both much much better.
S3 for legal long term Archive ( no need to get it back in DR ) is fine , but i would never go for a S3 replacing Tape.
Having a local S3 is risky as having local Storage , with admin rights the system is gone within minutes . All the immune stuff does not help if the Storage behind gets wipped out .
just my 2 cents on this