I think that's the point of material design. It's the design equivalent of egoless programming. You should not be able to tell who wrote/designed something if it is done properly.
It's also hugely beneficial for Google if all apps/sites get sucked into looking the same, so their platform becomes a platform, rather than a gateway to individual companies.
Beneficial for them, and dangerous for others I fear.
Beneficial for them, and dangerous for others I fear.