Apparently, I was wrong. Although earned income for the filing threshold and standard deduction, scholarship is now unearned income for purposes of the Kiddie tax. Reference: https://www.thetaxadviser.com/issues/2019/jul/kiddie-tax-unearned-income-scholarships.html
For most people, that's not a problem because the standard deduction covers most of it.
As to the 2nd issue; I've seen that discussion here before. The basic answer was: an RA is more student than employee.
