"no floating wreckage was ever found by any aerial or sea searcher"
Aerial searchers and satellites did spot debris, but couldn't examine it. Ships sent to investigate couldn't locate it. This was a very difficult situation- enormous search area and long transit times, plus the long delay before they even started searching in the correct hemisphere.
Historically it is not unusual for an airliner to be lost at sea without a trace, even when the search was started within 24 hrs and the approximate location was known. Example, the Varig B707 PP-VLU, which went down in 1979 approximately 200 km from Tokyo.
Consequently, I read nothing into the failure to find a floating debris field.