The bald wording of the regulation is what it is.

The courts have added to it over the years by various rulings such as compensation being payable for delays which was never in the regulation. They have clarified the calculation of the reimbursement of a downgrade and on the definition of various extraordinary circumstances.

The only way to get a change so that compensation (rather than duty of care) is paid to people who would rather rebook onto a later flight than be downgraded is to take it to court and eventually the ECJ to rule on the matter. Though I don’t think even the most consumer friendly judge would agree that if the passenger decides to extend their journey by taking a much later flight to preserve a seat in a particular cabin they should receive additional compensation.

one thing that is likely not going to change is airlines being forced to reimburse incidental expenses such as car hire and taxis, that’s what travel insurance is for.