text: "cid" on your screenshot looks too short (32 bytes in base64url?)
  
  atproto.com/specs/blob#b... 
  notes their CIDs are always version=1 (0x01), codec=dag-cbor (0x71) and multihash=sha-256 (0x12)
  
  hint: sha256 happens to produce 32 byte digest
  guess: API returns you the raw sha256 digest to save space