I'll answer only for me, and you'll have to do you. I wanna know. Knowing is what improves my motivation. If I need/want to be motivated to do 'something'....anything...that might help me to live another ten years, I'm gonna do it. Except with a bit more focus, learning, and enthusiasm now that I know what's going on inside me.
A CAC score is like a selfie. In ten years, you won't look like the image in the selfie because a selfie is just a snapshot in time. An instant. A picture. That's all a CAC score is. It doesn't tell you your score is dropping (for some reason) or that it's rising (for another reason), or if it's static. It's just a score. True, the score might reflect an iffy lipid problem in recent years (it has nothing to do with dietary calcium !!!!), but it might be some inflammatory response about something as yet undetected, it might be too many carbs in your diet, too much stress (cortisol, you can google 'stress and cortisol')...several possible causes. They can mostly be changed for the better, but you gotta know....right?
I went on a statin as soon as I was diagnosed with a heart arrhythmia. I ended up successfully treated for the arrhythmia, but meanwhile, all the workup diagnostics to see what the cause was only showed I have severe sleep apnea. All other chest x-rays, MRi, angiogram, radio-opaque dye treadmill stress test with CT scan (X2 over four years), not one of them showed more than 'minor deposits', the words of the gentleman who was moving the catheter inside my heart during the angiogram. A Doppler ultrasound of my carotid arteries showed I was clear (my dad was 100% blocked at 87 on one side, but his eldest son is clear at 70...go figure). So, my lipid panel had me on a statin right away, abut every subsequent test (no CAC done on me) have me with 'minor deposits.'
A CAC score will show you what is in place. It can sometimes be resolved by quite a bit with a change in lifestyle. I have read about some people getting horrid numbers, they do keto or carnivore for a year and their next score (according to them, not me) has them at 30 or something.