Stadia is very similar to what MS wants to do with Xbox Live as a service across the industry, but Google has the flexibility to make more partnerships, however with internet still lacking in most areas of most countries, data limit caps in place on most service providers, and the want for specific hardware for gaming still, I do not think the timing is right for this.
This could, however, dramatically improve the internet infrastructure, at least in the US and other countries with this issue. Google Fiber will have to expand to more areas and be affordable in order to support the service, which will force other companies to expand their reach into more rural areas as well as offer comparable services and pricing for internet. Then, everything will more ready for Stadia. I don't anticipate this to be the case for another 5-10 years at least. In that time, there will be newer versions of the service, Google can get more support for it, MS, Sony, and Nintendo will have made new decisions along the way and the entire landscape will have changed. With all decisions influencing each other, it is impossible to know the outcome of this right now. As another note, this does not necessarily apply to Japan. They are small enough of a country and already have a great internet infrastructure that Google may penetrate that market much faster, strongly weakening Nintendo and Sony.Last edited by zygote - on 20 March 2019