Not quite - "everything is a blob" has very different concurrency semantics to "everything is a POSIX file". You can't write into the middle of a blob, for example. This makes certain use cases harder but the concurrency of blobs is much easier to reason about and get right.

Personally I think you might actually need a DB to do the work of a DB, and you can't as easily build one on top of a blob store as on a block device. But I do think most distributed systems should use blob and/or DB and not the filesystem.