BMI is correct for about 80% of people. The biggest problem is for people that are very tall, as you are 2 standard deviations from average height it works less well. The muscular argument is a fairly weak one, as the extra weight even as muscle can still be bad for your skeleton (and many that say they are muscular aren’t 2+ standard deviations from average).

I’m slightly shorter than you, but the best I ever felt was when my BMI was on the edge of normal and overweight.