There are questions that were migrated from other sites, e.g. Stack Overflow.
These questions have a migration notice, e.g. Remove audio from video file with FFmpeg
(Sorry, I didn't know where to put the red freehand circles, because the whole image is the notice itself).
Now, such a notice may be helpful in the beginning, directly after migration. We then know that the question might not obey the rules of our site yet. However, after some time, the question should either be accepted as a valid question or it should be closed.
After 8 years, I personally don't care any longer where the question came from. So maybe we could remove the unnecessary clutter. It does not provide additional benefit any longer and just makes the site less usable.
I think 3 months of a notice should be enough.