This is based on user feedback from the Hebrew Wikipedia.
After you highlight some text and add a link, the text remains highlighted. Typing more text immediately deletes the link. It is possible to deselect the text by clicking after the text using the mouse, or by pressing an arrow key on the keyboard, but actually it's best not to have to press anything at all.
In Google Docs, after a link is added, the caret is after the link and it's possible to continue typing. It should be like this is VisualEditor, too.