The simple and honest response can be an automated email that says you didn't meet the requirements - you would be amazed at how many job postings don't even do that.
I can understand the justification for all of the other choices. But it doesn't mean I have to like it. The whole process is degrading and dehumanizing, and it's something that has gotten much, much worse in the last decade.
The GP said the quiet part out loud. They are so worried about lawsuits that they'd rather make the job market worse for everyone (including themselves) than risk a lawsuit over the most basic feedback. The product of a low-trust society.