StripImage also delete ICC image profile by default.
The resulting images seem to lose a lot of color information and look "flat" compared to their non-stripped versions.
Consider keeping the ICC profile (which causes richer colors) while removing all other EXIF data:
1. Extract the ICC profile
2. Strip EXIF data and image profile
3. Add the ICC profile back
The code is:
<?php
$profiles = $img->getImageProfiles("icc", true);
$img->stripImage();
if(!empty($profiles))
$img->profileImage("icc", $profiles['icc']);
?>