Not necessarily - how do you know that your capacity is less than calculated? Did you do a lab test?
It does not say anything about your (other) capabilities, like that you are a great climber or sprinter.
For instance, Garmin (Fēnix 5 and Edge 530) calculates a VO2max of 63, which is in line with my lab result. The last time I had it tested, it was 60 and that was October 2018.
I am 59 btw…