Parents dilemma - Laptops for Physics Major Freshman?

Let me chime in to say get a computer with a solid state drive. They boot up in like five seconds, versus two minutes.

Amen to that.
In fact, to save money, I buy a computer with the specs I need, and with the cheapest hard drive option.
Then the first thing I do upon receiving the computer is to replace the hard drive with an SSD. The “stock” hard drive is used for backup.
About MacOS or Windows, I don’t think it matters. I bought a MacBook Pro for my D when she entered college (CS major). When she started PhD program, the school gave her a Surface Book; not because the Surface is better than the MacBook, but because the school has a deal with Microsoft.