There are two sides to this coin: The user has earned this privilege legitimately, or this user has not earned this privilege legitimately.
Both sides of this coin say that this is acceptable.
Let's examine both sides of the coin using your User as an example. Since he is an outlier, we'll call him User Georg.
User Georg Deserves This Privilege
User Georg has spent hours composing two absolutely perfect questions on his SE site of choice. Over the course of five days, he receives the maximum possible rep points for both these questions, and is quickly granted Editing privilege, along with all the other privileges he has earned therein.
This user knows how to post these fantastic questions because they understand SE - they have read the rules and understand what this site is about. They know what they should and should not post, and therefore also know what other users should and should not post. And because of that, they are qualified to make edits without review, even if they've never made an edit before.
User Georg Does Not Deserve This Privilege
User Georg has abused the popularity of X to quickly write two incredibly popular questions. By some fluke, these questions remain popular for five days and garner User Georg 200 Rep a day.
User Georg has not read the help page, has not taken the tour, and still thinks SE is a message board. He is unprepared to take a critical eye to people's posts, and will make terrible edits.
However, there are two other types of users on the SE site that not only have the same privilege, but can revert his edits when they see them:
- Users who also have 2000 rep
- The person who originally posted the question/answer
User Georg is one person, and he may not know what a proper edit is to make on a question/answer, but the other 2000 rep users have taken the common, long-road approach, and have the experience on SE to recognize edits that are needed. The user who owns the post, regardless of their privilege, can also edit it as much as they like and revert any edits, good or bad, that a 2000 rep user makes to their post.
User Georg Is An Outlier
While it is possible for a user who has 2000 rep to make bad choices, it is an accepted risk that is part of the SE system. It is also understood that other users who have 2000 rep work to negate that risk, and that a user has control over their own post so that they can immediately revert any edits that they disagree with.
In short, while User Georg might be a terrible user outside of his two highly-upvoted questions, he is an outlier, and in writing the rules in general for SE, he should not be counted.