An eight-sloops-per-year program from the late 1920s could have produced roughly eighty in service and more under construction by 1939. Treaty permission was not the binding constraint; successive governments would have needed to fund those hulls without using them to replace destroyers required for other missions. The extra sloops would probably have been useful, although the counterfactual remains uncertain. Carriers, cruisers, destroyers, and battleships also took longer to build, which explains why they often received priority under tight budgets.
Notable Point · 29:31-33:09
The treaty-exempt sloop fleet Britain did not fund
Treaty rules permitted a much larger annual sloop program, but budgets and competing destroyer and capital-ship needs prevented Britain from building it.