Moped-enabled crime

Because it just doesn't work.

1. Thieves are clued up to them.
   
2. Response times are rubbish
   
3. Authorities still won't do anything about it. Motorcycle theft, like Bicycle theft, is a very low priority.
   

So rather than a concrete proposal (ha) to stop moped theives as close to the crime as possible I think you are advocating some trail of victims approach?

So maybe if they catch the criminals a few hours/days/weeks later subsequent victims can get a warm glow to know that the crime committed against them among a score of others are 'asked to be taken into consideration' when a guilty plea has been entered.

As others have said, there isn’t policing power to bother following it up.
They literally just won’t turn up if you give them the exact address of the stolen bike.
A lot of trackers won’t work if the bike is simply stored under a roof like in a garage.
It is very low priority despite the fact that they’re often used in higher priority crimes.