I honestly think ATS are a pain in the ass simply to filter out the people who won’t deal with bullshit. They want people who will live with bullshit working for them because the org is (always) dysfunctional.
Alternatively… their HR technology team is just trash because it’s run by HR and not someone who knows technology. Seen it plenty of times where shadow IT is being run by people who don’t know what they’re doing beyond “we need this thing.”