Nest's "enhance" cropping/zoom feature increased details but at the expense of cropping the field of view, which many home/DIY users may find confusing or objectionable.
Though its no different than the way a mechanical zoom behaves; greater detail at the expense of FOV.
If this type of "digital zoom", i.e. one achieved by incorporating a sensor of far greater resolution size than the stream it delivers, becomes more popular, "digital zoom" may rival physical zooms, without the moving parts and all the extra glass.
Though using a higher resolution imager tends to reduce low light and WDR performance, so there is that tradeoff. Also, there is only so much higher resolution one can for using digital zoom, i.e., you cannot use a 100MP imager and then digital zoom for an HD output stream.
To reiterate, that 'enhance' feature is not new, check our Dropcam Pro Camera Test where we cover that 4 years ago.