I think both work. Mechanical is more practical but as someone earlier said, just because your degree is in aero doesn’t mean you have to be in aero.
I work for a global 100 company. My former sales vp was an aero engineer major.
The skills will travel well.
At some you can major in one and minor in the other as well…get a little focus. or you can major in meche -but hope to get an aerospace internship - happens every day.