In principle, you have to acknowledge that the manufacturers maintenance schedule is best.
The problem is that (in the case of light aircraft) the manufacturers created maintenance schedules for the US environment where following them is not mandatory. So, they were produced as a guide, not a mandate.
With 20/20 hindsight we can see that manufacturers schedules over maintain some components, skip others which should be included (hence Cessna SIDS) and has never been updated to consolidate AD's. It also does not take into account better material and quality of parts available now compared with 40 years ago.
This works in the US system where departures from the manufacturers schedule is allowed, the FAA credits A&P mechanics with having some brains and there is a network of FAA offices which are approachable.
Australia's military based, centralist, bureaucratic system that has a culture of not trusting the competence of pilots and engineers can't live without a mandated list.
Hence schedule 5 was born. I reckon it was written around the maintenance requirements of a Tiger moth. Its loose and not very prescriptive and can be quite inappropriate - but strict adherence to manufacturers schedules is expensive and frequently inappropriate. Schedule 5 is the only mechanism we have to allow an element of common sense freedom.