It is not very likely that U 12.10 will run on all Pentium M as they do not support non-pae kernels anymore - problem solved
Sigh (again) Pentium M was just an example.
The point is, which are the CPUs Canonical was targetting with Unity 2D? Since that has been replaced by Unity 3D via LLVMpipe, is the replacement working on that same hardware? A reviewers task is to check if a piece of hardware or software works in the intended environment. The intended environment for Unity 2D was not high end hardware. Neither it's replacement's.
Is it really that hard to get?