In Canada the traditional solution to this is to assign the headcount to a job they're incapable of doing. Either a job above their skill level, or a job where the required quotas are unachievable.
You reassign the headcount, and then when they fail, you fire them for just cause.
One has to be careful though, because if the re-assignment is too different from the old job the headcount can claim "constructive dismissal". So you can't do this by assigning a "coder" to sales, or a salesperson to accounting. You'd assign a coder to a different type of coding. That way the headcount doesn't have a case.
It is ruthless.
They need to address the issue that older employees who are targets of the RIF can claim discrimination when they can show that there is still demand for their skills.