Making another (stupid) law won't change that
The problem is that in some cases this law, stupid as it might be, probably will stop some illegal charters.
The difference in cost between a private operation and paying an operator to manage the aircraft will be much reduced. The unfortunate thing is simply that they made this so just by increasing costs to private operators, and did not even consider reducing costs to AOC holders.
Of course any professional management company, especially if it has an AOC and executives have signed Form 4, is far less likely to sell illegal charters. The ability of the Authority to shut down an operation, or at least demand serious remedies, is far more a deterrent than the £250 fine one company my previous employer managed to prove to be flying illegally was given.
So an owner who wants to charter the aircraft out might as well put it on an AOC, and charter it legally. At the very least the premium for doing so is reduced, and therefore so is the incentive for chartering illegally.
There could have been other remedies that would have been far better for reducing illegal charters. However they would need co-operation of private and corporate operators who never took this problem seriously.