I’m not going to speak like “we have superpowers” or stuff but this is not as common as most people here think.
My guess this ability is confused with something else.
We are talking about an ability to change the focus at will or better our eyes adapting in different situations. For like when you put on your grandpas glasses on, you still see clear. Or your friends etc. No matter how big the number is, you just see clear with any numbered glasses.
How many people can see clear with another numbered glasses as they see with none? Tell me how common is that.
aı have a different aproach;
My theory is that actually our eyes are faulty and the blurred state is actually our default state of the eye. So we should use glasses to fix our blurry vision. But the ability to control (adapte) the cillitary muscles just fixes that problem for us and lets us see clear. The bonus is we can blur at will and see clear on every glasses.