I never needed one when I fronted a function band, and I was on guitar too.
one of my main hates of rehearsals is when band members turn up not knowing their parts. It's a rehearsal, not a learning session. I have the same view for all instruments including voice.
Learn the parts at home, so the rehearsal can be used properly. The only time I had lyric sheets at a rehearsal was in an originals band when the words were being tweaked all the time.
Aesthetically the floor based autoprompt is far less ugly than a stand, and to be honest it looks like a monitor rather than a stand, but it still shouldn't be necessary.
The references to music stands being "props" make me laugh - they are nothing of the kind. They are crutches!