Didn't really fail, GeForce Now is still available and working well. Stadia was abandoned by Google but worked really well for the ones that had good internet and lived close enough to the data-centers.
The bad part is needing to live close to a big, expensive, GPU-heavy data-center, but if mobile GPU's are getting that good, maybe in the near future we could have single servers or small racks serving a few dozen to a few hundred players, that would be much easier to co-locate, grow as needed, and improve latency.
The bad part is needing to live close to a big, expensive, GPU-heavy data-center, but if mobile GPU's are getting that good, maybe in the near future we could have single servers or small racks serving a few dozen to a few hundred players, that would be much easier to co-locate, grow as needed, and improve latency.