This has not changed. The difference is at what point the mail was scanned.
If the mail is scanned and detected at Transport Scanning then we get the full EML file - that's what we quarantine - the eml file can still be downloaded and viewed in all outlook versions since 2010 (honestly can't remember if Otlk2007 can view emls)
If the item was scanned at Exchange VSAPI level - then Microsofts VSAPI gives scanner the actual file itself so that how it has the separated item to quarantine.
Your examples show a Transport Scan detection and a VSAPI Scan detection.