Sadly, many countries have moved to multiple unit trains to avoid wasted time shunting.
Motorail in the UK used to be a few carriages tagged on the back of (usually) a sleeper train. There were all kinds of issues with the time it takes to load and unload safely at either end and the option to unload en-route is largely not there.
In the UK, a lot of space beside stations was also sold off so not all stations could support this any more (I guess you could build additional stops)
I think like moving freight by train, if there was a minimum level of demand, it would be worth the investment but until you invest, you don't really know what the demand is. In the UK, probably only the longest journies would be popular for taking cars by trains since most people would rather then drive for 4-5 hours than have the hassle and expense of the train journey.
Motorail in the UK used to be a few carriages tagged on the back of (usually) a sleeper train. There were all kinds of issues with the time it takes to load and unload safely at either end and the option to unload en-route is largely not there.
In the UK, a lot of space beside stations was also sold off so not all stations could support this any more (I guess you could build additional stops)
I think like moving freight by train, if there was a minimum level of demand, it would be worth the investment but until you invest, you don't really know what the demand is. In the UK, probably only the longest journies would be popular for taking cars by trains since most people would rather then drive for 4-5 hours than have the hassle and expense of the train journey.