That kind of tool will give you accuracy without precision. There are so many unknown assumptions involved that a model like that is going to give at most qualitatively correct results.
People who model the effects of climate change, like Nate Silver and the 538 crew, run thousands of simulations and present a summary. Even then you can get hung up on the "unknown unknowns".
For instance 1970s estimates of nuclear reactor accidents assumed the main risk was that the pressure vessel was going to burst. That's an easy risk to control, so you hardly ever hear of a pressure vessel bursting at a chemical plant, but all the time people blow up or suck in storage tanks that can't handle 1 psi of under or overpressure.
Now really a legacy nuclear power plant melts down 100% of the time if the power goes out and they can't start the emergency generators. That happens a lot more than bursting pressure vessels!
I'm not saying someone should throw a model with 100 parameters and say it's the truth. But you could incrementally build up a model for questions like "should we close schools and when", refining it step by step and getting a range of outcomes, a probability distribution. Sure, the precision is still limited, but it's much, much better than how the discussion looks today: "oh, our government decided to close all schools for the next two weeks, I guess that buys us a couple of days, so we're maybe no longer 3 weeks behind Italy, but 4". Because that's the level of the discussion on the smarter end.
My point is: we have the tooling necessary to talk about this problem better, more accurately, more precisely, in real-time, and to cover more angles simultaneously - which would lead to better decisions. But we're not using it. At least not publicly.
(This is a part of a general issue of mine, that we absolutely suck at having any kind of data-based discussion; best what we do is exchange badly made charts and context-free data points. We should be exchanging and discussing whole dynamic models. But I suppose this wider issue can wait until we're done with the coronavirus mess.)
We’re in a real situation where choices (or the lack thereof) will have major consequences. If the best estimate we can make is a rough one, it’s still sensible to use it as a guide for our actions.
People who model the effects of climate change, like Nate Silver and the 538 crew, run thousands of simulations and present a summary. Even then you can get hung up on the "unknown unknowns".
For instance 1970s estimates of nuclear reactor accidents assumed the main risk was that the pressure vessel was going to burst. That's an easy risk to control, so you hardly ever hear of a pressure vessel bursting at a chemical plant, but all the time people blow up or suck in storage tanks that can't handle 1 psi of under or overpressure.
Now really a legacy nuclear power plant melts down 100% of the time if the power goes out and they can't start the emergency generators. That happens a lot more than bursting pressure vessels!