Canroys were actual companies. US Trusts are not companies. There are no operations or employees.
The unitholders already are taxed at ordinary income rates.
Seems the only way they could increase revenue from trusts (apart from raising ordinary income rates), would be to eliminate the deferral aspect. But that would mean elimination of depletion and depreciation deductions and taxation on return of capital. That would impact just about all industry and would bring investment in industry to a halt. Hardly seems likely.
No, CanRoys used to be 'trusts' and Canada's parliment changed the tax law forcing Canada trusts to convert to standard corporations and be taxed. That change took away the attractiveness of CanRoy oil trusts. Look it up.