@scy You ask if they can "just skip it" but the issue is that when you're listening to the alt text of an image being read out and it gets to something like a URL there is no way to know 1) how long the URL is going to be, or 2) whether there is still useful information on the other side of that URL. The same would go for something like copyright information.
A sighted individual can look at a paragraph and instantly have that context. That isn't available through a screen reader.