On occasions I have seen people present and have an assistant operate their slides for them.
I think it’s a great idea if it’s done right. To me, that means making it seamless so that the audience isn’t even aware that someone else is involved. I don’t like it when the presenter has to keep saying “Next slide George please.” It breaks up the flow of the presentation and it would be much better if the speaker was to use a remote control to move the slides on themselves.
In my view, if you’re going to get someone to operate your slides then rehearse with them until you’re both confident and comfortable and they know exactly when to move to the next slide without having to be prompted. Your audience will be impressed and the presentation will look so much more professional.
Here’s a very funny example of just such a situation from Rainer Hersch, musician and comedian. In fact, my son Rob worked for him on a couple of occasions doing just this kind of thing following a series of rehearsals.