Some of the trimmers make specific mention that they're not designed to be made "fun" - another word for easier to use = electric motor driven.
'Course maybe I'm tyhinking of progressive presses - 550 destructions makes mention. I'm probablly off-base.
Frankly, I don't see how that'd be a worry long as you do the "manual" part of setting the trim length correctly & do a few checks here 'n there to make sure you're not making .30 carbine cases out of .30-06.
One problem I could envision would be the Tool Time/Home Improvement trimmer .... seems like you'd want to keep the revs down some is all.
Piece o' plywood to fixture the whole shebang on (Or just bolt to the bench), dump the handle/hand crank, fixture motor to the trimmer shaft & off ya go ....
Been meaning to get around to this for 40 years ....