You are suggesting removing the existing 'old' infrastructure where you can plan for things,
No I am not suggesting removing things... there will always be demand for traditional hotels and commercial transportation arrangements. These things will likely have a higher price, since services such as AirBnb and Uber will inexpensively service people who don't need pre-defined committed and guaranteed arrangements.
As the demand falls, some but not all players go out of business...... But entities like businesses still need guaranteed hotel rooms and transportation services, so there is still a market for them, just a much smaller more niche one.
to replace it with a host of 'disruptive' systems where everything is just-in-time and tied to demand, for the benefit of companies like Uber
No.... it is for the benefit of people actually. The presumption is services like Uber generally lower not increase costs, which is the entire point; the costs are lower by not having artificial scarcity. But meeting unpredictable demand is still a problem; it's even harder for Taxis, where the result of demand surge is just that you don't get a ride at all, so it's not like this is just an Uber problem.