A filter designed for by-pass use should simple clog up and stop passing oil. That makes it a fail-safe design.
For a full-flow setup that would starve the engine of lubricant. So a by-pass valve is required. But how good a throwaway by-pass valve can they make for $3? They can leak, meaning you have no filtering. Or they can stick closed meaning that your engine can be starved of lubrication. The failure they are designed for is when the media becomes clogged, then the valve opens to let oil to the bearings. But that oil is going to have a bunch of the crud that was clogging the filter. You don't want to have that happen, so you must be cautious. And that means replacing the filter at every oil change.
The bypass system simply stops passing oil from the pressure gallery to the oil pan if the filter becomes clogged. Not a real big deal. So you can run the filter until it becomes clogged. And that can be many oil changes.
And since you don't want a huge flow of oil through the bypass, you can have a finer filter media. End result, with the proper selection of filter, you can get finer particles out of the oil than a full flow filter ever could.
So, I think installing a filter designed for full flow in a bypass application gives you the worst of both worlds. That was the reason I was wondering if the Amsoil (or equivalent) spin-on bypass filter could be used on the adaptor shown. That gives you the best of the bypass design but with the ease of change of the modern style filters.