HR tends to be the first line of defence between a job seeker and a hiring manager. The majority also conduct the phone interview and occasionally the first face to face interview.
Finally, who do you think hires other HR staff? So, yes. Human resource people are hiring managers. More so than most.
HR tends to be the first line of defence between a job seeker and a hiring manager
From my experience (longer than tptacek's) there are BFE (big freaking enterprises) that use HR to screen, but in every one of those, if an external applicant could find a hiring manager, HR reduced to a pro-forma deal.
Even at the executive hiring level, if HR is meaningfully involved, it is with a specialist hired to do nothing but that.
As a "first line of defence" they are the opposite of qualified. External candidates and internal hiring managers find ways around them if they are at all involved. Otherwise, the result is not filled with qualified folks.
We have HR. They don't screen.
I might suggest ratcheting back "incredibly uninformed".
The vast majority of established organisations with 100+ staff have a HR department and in Europe, the HR department usually screens CV's and are regularly involved in phone screening and/or first stage interviews.
This was true even when I managed hiring at a company of 50 people or so. At companies smaller than that, I've usually been the one to have a first look at resumes for my team.