Yeah, it's not a big imposition to carry ID most of the time, but... This is also the thin end of the wedge to having to carry ID wh n you go for a walk, or a swim at the beach. It is only seen a necessary for the Stereotyped Lycra lout flouting the rules. I shouldn't need ID to cruise down the local path with my kids, what harm am I going to do there? I shouldn't need to carry ID to pop over to a mates place and give him a hand to load the camper, and I certainly shouldn't need it to ride down to the amenities block from my campsite or down the block to the beach on my summer holiday.
Having to carry, or even hold, a licence doesn't stop the idiots on the roads, just watch a few episodes of highway patrol or rbt and you can see that if a driver doesn't want to give the police ID they don't, they get taken to the station and it goes from there, fine or not. Same for cyclists.
It's the incidental cycling it will hurt, not the stereotyped louts. We should be encouraging incidental bike use to help alleviate motor traffic. Make it easier to get to the local bowlo for a meal, down to the post office to pick up a little parcel that the courier didn't bother to get out of his van for, easier to follow the kids to school on a bike and a hundred other examples.
The other thing that should change is to allow cycling on the footpath. Helps those less confident to ride on the roads. I can't 'get out of the way' on the roads if I can't ride on the footpath, even if I want to - I don't want a fine and I don't want to be hit by an impatient motorist who can't wait a few seconds to give me some space on the roads and pass safely. While we are doing that we should be rolling back the helmet laws on pathways and residential streets, like the 50zones I haven't fallen off a bike in years except for high risk stuff like riding fast or in the scrub on MTB, there are millions of kms ridden by responsible adults around the world without a stack causing a head injury.