I can't set rules, because I'm not an employee. So this answer is just my thoughts on whether attribution should be given, not on whether it is required.
My theoretical side says it probably won't hurt to disclose, it sets a good example and won't hurt until all the dust on what place (if any) machine-generated content can have on the network is settled. What if the LLM makes a mistake or a particular LLM consistently makes many? In such cases, it would probably be nice to know which LLM did it, and it might help pick out problematic LLMs if more of them arise. It never hurts to do the best you can, to give as much information as possible, so add a disclaimer/attribution, for sure.
My more practical side says I've been using Grammarly a lot to help me with my English, and when I start editing a post, sometimes I edit a few things more that I hadn't noticed, but Grammarly did. Yet I don't add a disclaimer that Grammarly was responsible for those particular parts of my edits. For a bit of fun, let's see what Grammarly makes of that first quote in your question:
On the enormous territory of the park there are lakes, rivers, canyons, and caves. Lake Yellowstone, one of the greatest alpine lakes in North America, is located in the center of Yellowstone caldera, the greatest supervolcano on the continent. Caldera is considered a dozing supervolcano; he erupted with enormous force several times over the last two million years. The greater part of the territory of the park is covered by hardening lava; in a park, there is one of five existing in the world of geyser fields.
It's actually worse than what GPT made of it. Grammarly isn't as flawless, so I would still be forced into doing manual checks, and manually doing a few more fixes. Copy-pasting a result from an LLM doesn't really force you into double-checking as much as using Grammarly does. And, another edit after I made one with the help of Grammarly could make sense, because we both may have missed a spot.
Also, Grammarly only works because I already started editing, after recognizing the post needed work. And if the post is already as correct as Grammarly can recognize, it just doesn't suggest further changes when I mash the edit button: I get no 'easy' or 'free' edit from it if the post is already 'good enough'.
BUT! Just for fun, I've run your second quote (the one GPT already corrected, and for which Grammarly gives me no suggestions) through GPT again, with the prompt "Rewrite this to standard English". This is what you get:
The park covers a large area and has lakes, rivers, canyons, and caves. Lake Yellowstone, which is one of the largest alpine lakes in North America, is located in the center of the Yellowstone caldera, which is the largest supervolcano on the continent. The caldera is considered a dormant supervolcano and has erupted with great force several times in the last two million years. Much of the park's land is covered in hardened lava, and the park is home to one of the five geyser fields in the world.
So, basically, even though the quote didn't need changing, the LLM followed my command nicely, and gave me an edit that's over 6 characters long and can be submitted to SE with no problem. It is still flawless according to Grammarly. Which means it's time for a party! 'Free' edit credit without me having to do any thinking/checking! 'Free' post bump and visibility! 'Free' visibility for me through my user card on that post as well! They all may seem relatively harmless, but they could all be abused: edits give badges and count towards the candidate score in moderator elections, meaningless edits aren't allowed so using them to bump a post for more attention certainly isn't, and the user card visibility could be used to push a certain username (think spam, or political opinion) in front of everyone. So there are certainly downsides!
I wouldn't outright ban using GPT to correct quotes like your first one, which, admittingly, does need a lot of work. And GPT did a nice enough job of making it a nice quote. But based on all of the above, I think the following should be the absolute minimum requirements for when you do use GPT or any LLM to edit posts:
- Don't just copy-paste, give a command, and copy-paste the outcome back. Manually check it. When I use Grammarly to edit posts, I do the same.
- Abide by the SE guidelines for edits. In particular, make sure your LLM doesn't do anything that's not described under the 'When should I edit posts?' section.
- Make sure the post needs editing before firing up the LLM. As I showed above, it will follow the command to rewrite, even if nothing needs to be rewritten.
- Attribute the LLM. It makes it easier to spot patterns of any problematic LLMs. It also helps moderation: If you state you've already used an LLM, any user that shows a pattern of making more meaningless edits using an LLM (they will probably not disclose but be able to be spotted) after yours for whatever reason doesn't have the excuse of 'I couldn't know!'.