CPV and CPM describe the same relationship at different scales: a CPM of two dollars is a CPV of two-tenths of a cent.
The distinction that matters is not the arithmetic but what counts as a view. Platforms define a view differently — some count a fraction of a second, others require several seconds of watch time. Comparing CPV across platforms without checking those definitions produces a misleading number.
For a brand, CPV is most useful as a directional comparison over time on one platform, rather than as an absolute figure compared across them.