Carlton Reid, the guy who started the trade website BikeBiz, is my source for this, and his is a name to look out for, his writing is consistently good and his advocacy based on a knowledge of history. I am just paraphrasing what I have learned from his telling of the early days of the CTC (Cycle Touring Club).
There were many cycle touring clubs, and this was how men met women without their mothers being around!
The trains connected communities as never before and what we call the 'A roads' that connect towns had nobody using them, simple as that. Why would you go on an arduous journey that would take all day when the train would get you there in twenty minutes?
At the time there were no local authorities to look after the roads, it was each parish to its own, with the locals doing the work. Toll roads were the solution to the problem of maintenance, and toll roads were the 'A roads'. When they no longer had customers, due to the trains, they were done.
As for the bicycle and the reopening of roads, this had a lot to do with men chasing women, before the bicycle you were somewhat restricted to the gene pool in your village, with the bicycle there were neighbouring villages. It wasn't all about getting to the factory for work, there was this huge leisure/dating aspect to early cycling culture.
Trains were 10x faster than horses and men - at walking speed - on rough roads. The toll roads just withered and died. Confronted with a mountain, the train would just blast through, whereas the road would be a treacherous mountain pass, no tunnel, cutting or massive bridge provided. Trains were rocket ships.
Before that, canals had their own quirks of geography, with much of it to do with feeding or resting horses. The signs are for the next horse stop, not the nearby town.
With many a British town the town centre can be dated by when the canal arrived and when the railway arrived, since the buildings in the town centre start in local stone, then you get slate from the canal arriving and then brick, because the train made it to town.
It is incredible that so much of the final mile was by horse and cart. Only with 21st century goggles on does your idea of induced vehicular traffic make sense, trains were just too good.