What's the point of a google coin?
If it's centralized and controlled by them, that takes away a huge benefit of bitcoin so why would anyone switch over to google?
So de-centralisation is the most important property of bitcoin? People will transfer to any cryptocoin that's more convenient, if that's Googlecoin, they will go there. de-centralisation is only an issue for certain political aims.
I didn't say "most" but some would say it is... it is definitely a big advantage of bitcoin. All my information AND my personal wealth controlled by google? No thanks