I wouldn't say no distributed object storage system is particularly tuned for that. Facebook's haystack and systems patterned after it can work very well for tiny files.
Sorry, I meant for public cloud providers. You're right that Haystack would be fine for small files, but IIRC (and skimming the paper again [1]) it stores the entire photo inline in a single Needle. That's fine for photos, but not for people that want to say store a 5 TB single object (and for Facebook, they could just reject photos larger than say 100 MB). Still, good idea!
[1] https://www.usenix.org/legacy/event/osdi10/tech/full_papers/...