They would be better off, and so would the company and society at large, if they were put into a new role (at the existing company or a new one) that actually provided value.
Actually we do it, and it helps. In fact a large part of current jobs is like that, BS busywork jobs.
The reason it helps is, as I see it:
1) Productivity/automation is well up...
2) More people than required are available to work
3) -- On-demand re-education of the kind needed to fit actual needs (e.g. for programmers), can't / ain't gonna happen, it's a pipe dream at the speeds required and for the populations concern
4) -- and even if it was possible, it would just cover a small fraction. Even with all job needs covered, many people are not needed to work anywhere, period.
5) BS jobs hence serve as a distribution / welfare system / kindergarten for adults
6) -- but allow us to not call it "welfare" and to include more than the poor, and have them keep their dignity (since we sneer on welfare recipients)
7) -- and keep from having a huge unemployed mass revolting or making society Mad Max
Instead, companies need to be forced to do it, by law -- like they were forced to stop child labor, to have safety laws, to 8 hours workday, etc.