Using the following at the end of my scxript
$spreadsheet->getActiveSheet()->getColumnDimension($column->getColumnIndex())->setAutoSize(true);
distorts (stretches) images currently contained in the spreadsheet and originally placed over cells, not it. Contrast this with using the Excel Format -> Autofit Column Width function which works perfectly.
Is this a bug?
There's not much information on Google for this but everything I tried either failed or produced the same result