I think they're uninterested because they have a documented and supported userspace VFS API. The problem is, it's really designed for cloud drives and so deeply

I think they're uninterested because they have a documented and supported userspace VFS API. The problem is, it's really designed for cloud drives and so deeply assumes a sync model. Works great for the intended use case, much better than Fuse but if you want to do something unusual, not so hot.