That does not sound right to me because I don't recall any changes between the two version in this area.
You should compare all the settings in the File > Interoperability > DXF-DWG Translation Setup Dialog between the two versions to see if there are any differences that might cause this.
In the "Settings" panel, some of the field that may influence this:
Save Options > File Format
Attributes > Fills > Methods > "Export all Fills as SOLIDS"
Attributes > Fills > Methods > "Export Fill Backgrounds as Additional solid Hatches
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