As quoted from the linked post.
It looks like you’re part of one of our experiments. The logged-in mobile web experience is currently unavailable for a portion of users. To access the site you can log on via desktop, the mobile apps, or wait for the experiment to conclude.
This is separate from the API issue. This will actually BLOCK you from even viewing reddit on your phone without using the official app.
Archive.org link in case the post is removed.
Is it better to overwrite comments and then delete them, or is just overwriting with whatever message I want to leave then deleting account accomplish same goal of making comments useless.
Reddit doesn’t (at least as far as I know) store a history of edits, so what is saved on the database is what your comment literally is. The reason people suggest overwriting comments is because the comment itself has value (for a variety of reasons), so overwriting the comment with something valueless (in the sense that it has no value for Reddit) is better, so the database itself is updated with that valueless comment.
After that whatever you do with the account is up to you.