It's not true that no one else has complained in 7 years. Here is someone who wants Opus to stop modifying JPG files.
2022-01-23 filewrangler
When writing to "descript.ion" files, I think it would be preferable that the image/file is not modified.
Labels are great, but like you said, they don't support free text, and cannot be used in other programs like 7-Zip.