Well a lot of this is the result of local authorities and campaigners trying to 'Canute' the car.
If bus and other public transport networks shifted to support the places people want to go, rather than the legacy town centre, we'd be in a much better spot.
New developments should include dedicated public transport routes in their fundamental design (nothing in the way).
I also feel money should be put into proving low capital cost automated or semi automated transport solutions and making them available for widespread deployment
From a transport perspective I think we should probably encourage or outright develop properly managed home delivery system that can eliminate many shopping trips entirely.
The psychic impact of the 'high street' remains powerful, but I think webe reached the point that political obsession with it is counterproductive.
Trouble with out of town is where do you run the busses from/to ?.
Do you provide a fast and frequent link to the nearest town centre so that people can connect with existing transport. That means an extra leg for many peoples journeys.
Or
Do you completely change the bus routes to radiate out from the out of town shopping which then means less flexible longer distance public transport like railways is left behind at the old town centre. And the bus routes no longer radiate from the town centre.
Or
Do you just bite the bullet and thoroughly re-develop town centres ?.
(to be fair Croydon has half heartedly done that. Demolish and planning blight but no new build)
The reality I see is we have a few token bus routes provided to the out of town shopping area. Most people use their car be it ICE or EV. The town centres are less polluted because no one wants to go there by car. Witness the smell on the A23 outside central Croydon compared to the town centre.
Talking of EVs. Many (most ?) of our out of town shops around Croydon now have parking restrictions - typically time limits. This seems to have appeared at the same time as EV charging has appeared in the same car parks. I wonder if there is a connection (no pun intended) with EVs perhaps being left all day ?.
(fast charging makes me assume not).