Having worked as a countryside ranger in Scotland where we don't have green lanes it seems strange to me that the folks daaan saaaf have seemingly never heard of the honeypot principle. It is true that green lanes get badly eroded by traffic. It is also true that this happens on a very thin strip of land. I'm willing to bet that a larger percentage of England and Wales is covered in astroturf than is used for greenlaning.
I believe that the users of green lanes have to be taxed and insured. This is a good thing. It allows a line to be drawn between legitimate and responsible recreational use of 4x4s, and trail bikes and the like. In Scotland, although there are a few places where there are accessible off-road routes and there are pay and play sites there is far more baying from illegal off-roaders that there is nowhere to go. I know that the Forestry Commission in Scotland who have a few forest drives that you can drive down are considering opening up more of their forestry tracks to allow more long distance off-tarmac trekking than is currently possible.
Honeypots are used all over to protect other areas of countryside. Ever noticed that its really easy to get up some of the Alps and pretty much impossible to get up others? Green lanes weren't originally designed as honeypots, but they work as such. Ramblers create plenty of erosion, disturbance to wildlife and nuisance to commercial land users. So do dog walkers, horse riders, fishermen, and a whole raft of other countryside users. Problem is that they all want to ban everyone else.
People weren't complaining so much about 4x4s in the bad winters when folks were volunteering to take home helps to the elderly and make deliveries to remote houses. How short is the memory of a complaining bugger!
Of course there are irresponsible folks in 4x4s that are doing real damage to the routes and who should know better. There are also dog walkers causing sheep to abort their lambs, horse riders destroying footbridges, ramblers disturbing colonies of nesting birds, cyclists putting walkers in hospital. Thing is, policy making should be about encouraging responsible behaviour, not about a constant knee-jerk reaction to irresponsible behaviour. That simply doesn't work as the people who don't give a shit, really don't give a shit and they do not care that they are being irresponsible. Move them from one thing and they'll go to something else and be a pain in the arse there too.