I am only replying to issues that I raised. Typo in our comments. Ref to ATAG is appropriate, ref to AERT is not, other than as historical.
Several checkpoints refer to using operating system conventions.
The virtual machine interprets byte codes into something the OS can understand. The VM is operating system specific. For example, labeling a table as layout or something like that. It was my understanding of this section that if a standard accessibility API does not exist for an operating system, that the developer must create and use their own. However, if these features are not accessible, developers must provide an alternative accessible solution.