Hi Stuart, back home yet mate?
In answer to your question...those fish do not need more 'protection' than their stilwater cousins. So as you say, it is a nonsense. But that nonsensical situation was brought about by greed, which caused the closed season on stillwaters to be wrongly done away with. To do away with the closed season on rivers as well would only compound that wrongness. It wouldn't make it right...two wrongs never do.
The stillwater closed season was done away with at the behest of tackle manufacturers and fishery owners, to extend their profit making to a year round affair. The proliferation of commercials developed to take advantage of that, pretty well destroying traditional river match fishing in the process. I would hate to see them get away with it on rivers as well.
I am of course a hypocrite, because nowadays I have surrendered and joined the vast majority in fishing stillwaters during the river closed season....there seemed little point in not doing so eventually. However, my weakness does not make it right, and I would happily refrain again if the general closed season were to be reinstated. Just my opinion Stuart...which means you and I cancel each other out voting wise. Pretty much the story of my life to be honest.
Take it easy mate, and tight lines for next season
Cheers, Dave.