Or adding traction control STOPS it from being a supercar! Ha ha!
Circular logic gets you nowhere, Ian. As long as you can put down one finger on a WS and get accompaniment, apparently no number of REAL 'pro' features overcomes that handicap. Sauce for the goose...
You've got to remember that ALL electronic keyboards started out with the humble organ. Every last one of them. They ALL have their roots in 'home' organs (nobody made portables at the start) no matter WHERE they are now. 'Pro' arrangers like the PA2Xpro, T3, E80/G70 and Audya have far more features taken from pro WS's, samplers, synths and other pro type keyboards than they do from home organs... but that is their common roots. By YOUR definition, every single keyboard on the planet is a 'home' keyboard. You are going to have to do better than that!
If you can't make a definition of a 'home' keyboard that doesn't include those keyboards that even YOU classify as 'pro', you haven't nailed it yet. One finger chords? WS's got 'em. Pro's playing arrangers? Plenty of those here. Roots in organs..? The lot of 'em.
Have another go...