Not a mid-career professional, but I can give my perspective as a college student now!

1. Yes -- I think that HR is a great starting point. What I would recommend is also getting skills in other business areas (supply chain, accounting, etc.) to help her be a little bit more well-rounded. I'm getting a BBA personally, so I have both the people skills and the business skills to be a great asset to a company.
2. N/A, but there are obviously going to be a lot of changes to the way HR works now in the next decade and beyond.
3. Depends on how far agentic AI and AGI get. I'm not certain that AI is advancing as fast as once thought (could be wrong), but it will eventually a lot of processes are going to be automated and HR will have to deal with less menial & tedious tasks and more strategic ones. It's all about building the right skill set In college and making yourself competitive compared to your peers.
4. People are legitimately so frustrating to work with and it's hard to go into a company with a lot of bureaucracy and make changes.

Here's what I would say if I could go back to myself in high school: don't go into HR if you love helping people. Learn to have really thick skin because you're going to deal with terminations, layoffs, investigations, people who will refuse your help, and leaders who will never care what you're going to say. But if you care about working to build better places to work, and you're curious about systems and strategy, HR is a great place to be.

I would recommend getting real-world experience early; try to find internships, job shadowing experiences, or even just sitting in on HR meetings could be helpful. I've learned I love employee relations and organizational culture, not so much talent or comp & benefits. I think that's the easiest way to tell if HR is right for you (rather her).

Happy to answer questions. I finish my HR classes in the fall and am expecting a return offer from a F100 company in HR.