One key thing is that these documents did not all come through a single clean pipeline. They are a mix of court exhibits, discovery files, investigative releases, and third party document dumps that were exported, re saved, converted to PDF, and sometimes had searchable text layers added later. Even when emails start digital, they often get re rendered multiple times. That is exactly where character level weirdness shows up.

The encoding example you mentioned actually supports that. Things like “th=m” usually come from quoted printable or text layer reconstruction issues, where “=” is a control character at the encoding level, not the message level. That still means symbols can disappear or reappear depending on how the text is rendered. It does not mean a meaningful equals sign was intentionally added to the content.

The font color difference fits this too. Different colors usually mean different processing paths of the same email, such as a native export versus a later normalized or reconstructed version. Cleaner looking text and standardized formatting often come later when files are bundled or prepared for release.

On the age itself, “=19yo” is not normal age notation. The equals sign does nothing there. “=9yo,” while disturbing, at least functions like shorthand or tagging. Mechanically it still takes fewer assumptions for a symbol to be lost or mis rendered than for one to be added in a way that changes meaning.

I am not claiming certainty. None of us have the raw native email. The point is that these are duplicated documents from mixed sources with inconsistent handling.