I had the same reaction at first. The frame of the blog post is the decline in science reporting, but it is a pretext from which to hang this story correction before our eyes and made no attempt to deal with accuracy over time, as you suggest.

However, it was two corrections in one story, and they both seem to have been howlers. If these mistakes were made by the COVID beat reporter, that's important. A better frame might have been something like "Why I'm Skeptical of NY Times Reporting" or "Why I don't trust NY Times Reporting".