Correct with a slight caveat. The best have crazy velocity. They can afford to put a little less effort in gaining ground. Each foot of ground gained is equivalent to about one mph.
It makes zero sense to take more time to get rid of the ball. Zero.
Some quick math* comparing a 60mph throw to a 65mph throw, and I get a difference of about 0.1 sec for a 90' distance (approx. home-2B). The catcher would have to make up over 5' on the ground, with no time lost in the catch-release, to make up that 0.1 sec. My DD is making up twice that in her knee throws just by being quicker to get rid of the ball. Conclusion: Get that ball out of your hand as quickly as possible.
* My math skills aren't excellent. Maybe @pattar can sort it out if I'm a long way off.