They're great for getting benefits programs set up, making sure that the company's health plan is competitive
That's a higher opinion of HR than I have. They're good at telling people the health plan is competitive, but is it really? It's too complicated to really understand. As for the benefits program, how hard is it to fill out some forms at Fidelity? I've never tried, but I bet it isn't hard. And while HR set these up, HR doesn't actually understand them and absolutely cannot explain them.
Otherwise, yes. If one got to the in-person interview, they think you can do the work. The one that gets hired is the one they think will fit best with the company and coworkers and not the one who best knows the specific details of the work.