It's not clear to me that large-scale travel bans are particularly helpful. A travel ban is about containment — keeping the number of cases in a region at absolute zero. Social distancing and other local behavior changes are about lowering the rate of infection and slowing the spread of disease in an area where it exists.
The latter is clearly important because it lowers the number of people who simultaneously need medical services in any particular area. A travel ban can help that if successful and it medical resources are easily shunted from a region with zero infections to a region that has them.
But once you've got a single patient zero in a region, the travel ban is fairly close to pointless. The disease is going to start spreading locally anyway.
At the same time, the economic effects of a travel ban do affect the daily lives of lots of people. So I think it's reasonable to focus mostly on local measures and slowing the spread.
The China approach shutting everything done can further slow the spread, but at massively increased costs and long term risks of reinfection.
china did the things they needed to. if they didn't, the costs would be many magnitudes greater. it's clear that china's efficiency and response will not be able to be duplicated in the west.
Unfortunately, even young healthy people are a significant risk of death so there are few good long term options.
For example, there are lots of public gatherings that can't afford to stop voluntarily - or if they can, can't afford to pay their employees through such a closure. Tell cinemas to stop selling tickets for two months but keep paying their rent and staff and some will go bankrupt.
A state that wanted cinemas closed could inject money (or motivation) to make it happen.
Likewise with theatres, gyms, casinos, restaurants, music festivals and suchlike. Much less travel if there's nothing to travel to!
Italy has a nationwide travel ban right now. The goal is to avoid completely overwhelming the health services rather than to keep the rate at zero
In theory Milan should be the city with more infected people (in proportion) due to the high number of travelers and residents, it is not
Infection has spread brevi manu, travel bans have been implemented only starting from last Sunday (8th of March)