Nice work on the chair.
I don’t know if a bandsaw of that quality would be capable of repeating cuts to a higher level of accuracy. Depends on the wheels, the blade, your ability to set the blade to track straight, etc.
I’ve done tenons with a dado blade on the table saw, sliding jig upright on the table saw, router jigs, router table and finally settled on hand saw method. The handsaw method works best in a non-industrial environment. Cutting them by hand means that I can cut each tenon to fit the mortise, no requirement to plane all my lumber to same thickness, or even keep my tenon in the center of the board. I can be flexible as needed for the joint in question.
