On this particular example
I've rolled the edit back.
The licensing tag was on the fence there: it's valid to think either it should be there or it shouldn't. Since that's the case, side with the OP and use the tag they added.
Bad tag edits in general
If you see a bad tag edit, do something about it. If you're over 1k rep, you can freely edit - roll the ...
Wow. Are you for real?
I've noticed several instances if unilateral and arbitrary retagging
Retagging is unilateral by definition, unless it's done via a suggested edit. Arbitrary is an accusation against the retagger's motives for which you state no justification altogether.
As an example of this type of mis-behavior
(and more similar language)
I disagree. With a scope that is ever changing, it is pre-mature to request name changes.
Not all questions on this site will be about licensing. One of the main focuses, which sadly isn't coming to life fast enough, is the organization and marketing of projects.
If we continue to broaden the scope, the name change would be detrimental to the site's ...
The tags that you mentioned are created way before people ever come up on meta (that is, by the system itself).
on-topic: To signify and figure out whether a certain genre of question is allowed.
scope: To figure out why questions are on/off-topic, why, and for discussions about including particular subjects and topics within the site.
They overlap, yes. ...