You need all four in the context of databases and the architectures in which they live, where computation is separate from storage and concurrent updates are po

You need all four in the context of databases and the architectures in which they live, where computation is separate from storage and concurrent updates are possible. In the context of Rama it's different, where computation is colocated with storage and you have tight control over the ordering of events. It's probably easier to understand if you share a specific example you've dealt with in the past that needed a particular isolation level. Then I can explain how that would work with Rama.