Explanation
The definition turns on whether a reasonable person could mistake the result for a recording of something that happened. A stylised animation is generated and not usually treated as synthetic media for disclosure purposes; a photoreal person saying words they never said is squarely inside it.
Reading policies with this term in mind is useful because it explains apparent inconsistencies. Rules that seem to exempt obvious AI art while catching subtle edits are not inconsistent, they are drawing the line at realism rather than at tooling.
The common mistake
Assuming light editing is exempt. Materially altering a real recording, moving a person's mouth or changing what they appear to be doing, falls under the same rules as generating one from nothing.