Academics can be a good way to get extra merit.
But I will say there is one public flagship both my kids applied to that is ever more competitive. The music department warned they have no pull in academic admissions. There are parents wringing their hands on the family boards right now because their kid got through the competitive audition process and were admitted but then did not get in academically. Ugh - that has got to be heartbreaking.
Keeping academics in good shape really does keep more doors open.