Could not be the problem caused by the fact the tags contain only a number, and the software is interpreting it as a tag ID? In that case, the edit link is not understood to be for 7, but for the tag with ID 7, which (in the database) is the ID for commerce. I checked other edit links, and the only ones for which I have a problem are 6 and 7. I will try creating 5 and see if I have the same problem for that tag.
If I hover the tag itself, and I click on the edit link that appears in the drop-down menu, I am taken to
https://drupal.stackexchange.com/edit-tag-wiki/425; the other edit link, which takes me to the edit page for commerce is
https://drupal.stackexchange.com/edit-tag-wiki/7. As you can see, the difference is just the number that appears as last item; this means that the code handling those URLs is not able to understand if it gets a tag name, or a tag ID. More correctly, the code that handles those URLs interprets the number passed as last component of the URL to be a tag ID, and interprets a string passed as last component of the path as tag name.
The only solution in the short term is not to use numbers as tag name.