Generally, we all GIS users encounter this issue, especially in case of ArcMap while copying pasting excel table or inserting as object, it get lower resolution while printing.
I have tried using insert object, it worked successfully except one issue. Issue is that it not only add the required excel table but also the some extra rows and columns.
- ArcMap 10.5
- Excel 2010
- Windows 8.1 Core: i7-4770