I personally think you guys both have it kind of backwards. These Xbox SOCs are heavily optimized from every standpoint, inckluding cost and production rates.
Either way the cost of upgrading is immense because to be "fair" we are talking about upgrading an array of datacenters across the world all at once, unless you want to create tiers of power for different users, which is possible. Still super expensive either way, and I don't see how or why the Xbox SOC which MS puts into 10s of millions of pieces of hardware already and has absolute miniscule costs to produce because of that will be more expensive than what google is using.
an Xbox SOC is designed for MS to make as much cash as possible reselling it to an end consumer.
A cloud compute server is designed to be as good as possible, and to be run continuously, spinning up as many instances as it requires to mitigate downtime.
the line between GPU and CPU is extremely thin nowadays; GPUs are extremely good at computing the same thing over and over again, CPUs are extremely good at computing multiple different things without knowing what is going to be involved in advance.
Like, the reason consumer GPUs went up in price is because a thing they can do really well - redoing the same calculation over and over again - is literally whats involved in bitcoin mining, not pushing graphical envelopes.
Google wouldn't bother doing this if high end GPUs were literally only of use to AAA gamers; unused compute time for GPUs is going to be doing machine learning tasks until someoen wants to rent it to play some vidya.
