I think it needs far more vision than the usual "tax the motorist" approach that most governments and councils have adopted as panic measures.
I agree with you to the extent that you do need more vision, and other measures too, but that doesn't present charging from being part of the solution too.
It's exactly that kind of pretzel logic that has resulted in town centres such as Huddersfield for example dying a slow lingering death. If you want to compromise out of town shopping centres and the massive contribution they make to local economies in the same way, make it more difficult and expensive for people to visit. They'll just find somewhere else to spend their money.
I don't think your logic works. One of the biggest problems right now is the lack of a level playing field between traditional town centres and out-of-town places like the Trafford Centre, and what I'm suggesting (requiring all shopping centres to charge for parking, with the money raised going to fund public transport schemes etc.) would even that up.
Councils, as you say, use parking charges and other measures to encourage people to use public transport to get to town centres. But the trouble is - because the out-of-town places remain free, motorists simply side-step the charges by going to the out-of-town places instead. That is what is killing many town centres, and what I'm suggesting would actually solve that: If
all shopping centres were required to charge for parking - so that you know that if you choose to drive, then you'll pay similar fees to park wherever you go, then it's more likely that those people who are reasonably able to use public transport would do so. It also means that people are more likely to go to their local shopping centres, instead of driving miles away to get to one where the parking is free - so this would be to the
benefit of many local shopping centres, including town centres.
Sure, some people might choose to buy online instead - and if online retailers can serve those people's needs better, then that's arguably not a bad thing. The large numbers of people who are going shopping because they like shopping - will continue to do so, but would be more likely to do so locally, or in those shopping centres that they can get to without driving. Obviously, those who are buying stuff that is too bulky/heavy to take on public transport, or who live in places that require driving will continue to do so, and will use the paid parking - in the process perhaps making a fairer contribution to society to cover the various environmental costs that other people have to bear as a result of their car journeys.