I disagree. I think it adds a human touch to things, I've flown other airlines and found it ODD that crew do not do the safety demo.
Also it gives one a chance to have a quick look at the pax, suss out who might be potential trouble or who needs an extra bit of help during the flight. (Also, who might be best to call on as an ABP should the brown stuff hit the fan)
Handy too that if anything happens, crew are already in the cabin to deal with it if need be.
Just my opinion, of course
