Consider iterating text on media upload for alt text

[karmatosed]

This could be confusing both in what it does and linking to an external source. It might be a good idea to work on some ideas to improve the copy here and also linking.

[melchoyce]

Historical context in #41612

[hellofromTonya]

#51616 was marked as a duplicate.

[hellofromTonya]

Merging @garrett-eclipse description from a duplicate ticket #51616:

On Media Modals the Alt Text has a description containing a link 'Describe the purpose of the image.' that's a little misleading to new users. It feels less a description and information and more an action in that users click it thinking that's how one would describe the image but instead find it's just information.

Could a little (i) icon be added to denote it as informational. Or could we adjust the language;
_Alt Text_ describes the image purpose.
*Where just the 'Alt Text' part is links.
This i feel would take the link off the action word which is what currently makes the link feel like an action and not just extra information.

Love the concept of the feature just think we can remove the ambiguity of the link purpose.