What are we comparing to a digital keyboard? A top quality piano that is maintained regularly or a $1000 upright that gets tuned maybe once a year? And are we talking about players who can really tell the difference? 

Real pianos have real problems. They react to humidity, temperature, moving, etc. A digital keyboard will be consistent - now, I will wholeheartedly agree that it will be consistently INFERIOR to that top quality, top shape instrument, but if we set that 7-foot Hamburg Steinway at "100%", there are plenty of lesser pianos at "40%" that can be bested by digital instruments. 

Just because it's real doesn't make it good. Why do you think the jazz world got involved in the electric piano in the first place? Because the pianos in clubs were absolute crap. Oh - but they were real.

Not everyone is Oscar Peterson who had his personal piano transported all around the country. 

I suppose someone will next advocate for pump organs vs. Hammonds. Hell, let's do away with records and get the string quartet to play in the living room when we want music!