This seems to miss a reference to Zoned XFS, which is the Linux file system that actually looked into this kind of data placement at the file system layer. The paper includes numbers using RocksDB:https://dl.acm.org/doi/10.1145/3725783.3764399
In our paper, we only evaluated with regular XFS (see Section 10.3, “What happens if a filesystem is used?” in the arXiv version), but evaluating Zoned XFS would definitely be interesting as well.