Yes. Actually look it up. Lighter bats are used in training to increase bat speed. With swinging there are underweighting and overweighting training principles.
As far as throwing, you really should check out Tom House’s stuff. All of the top NFL QBs and many MLB pitchers work with him.
I don’t think you will change your mind because you have a fixation on this subject, but it might be interesting stuff to learn about.
Drew Brees (before retirement) and Tom Brady throw lighter balls in the off-season, just FYI