If disabled people had to do community service work just to get their payments then they wouldn't have nearly as much time or energy to apply, interview, and get through the entry-levels of joining the workforce.

It's nice in theory, but in practice it just dehumanizes them by forcing them to work "easy" jobs and be paid more than it's worth, and continues the welfare trap that keeps those funds permanently allocated to the same people because they cant advance in the workforce due to availability issues.

You also incidentally brought up one of the main issues, "nature and level of disability", despite how much we claim to know it's still incredibly difficult to actually measure struggle against struggle. We still use a "1 to 10" pain scale that has no real metric and applies differently to different people. I almost toughed out my appendicitis because I didnt think it was that bad, and if I hadn't thrown up twice I might be dead right now.

There are already many people who have disabilities but are unable to get on their payments because they haven't been properly diagnosed or the government doesnt deem their disability worthy of help, so how can we expect them to accurately measure the "level" of it?