That sounds like a solution I'd personally never even notice. Most of the devices I consume youtube videos on either do not show the video description at all (TV) or actively disencourage reading it (the official Android app currently requires one or two clicks to even see it).
In addition to that, re-uploads are annoying enough as is because content creators constantly need to upload old content due to changes in Youtubes policies or enforcement. New revisions for any minor mistake instead of an overlay would properly ruin the subscription page imho.
In addition to that, re-uploads are annoying enough as is because content creators constantly need to upload old content due to changes in Youtubes policies or enforcement. New revisions for any minor mistake instead of an overlay would properly ruin the subscription page imho.