I’m not sure that Hardware has the same moat as Service/Platform.
If (it’s a big if), NVDA get leapfrogged in hardware capability it will be trivial for the next generation of deployments to stop using them entirely (Google and Microsoft are already developing custom inference chips, as are others)
I don't think this is true. AMD's hardware, on paper at least, offers the same or better performance than Nvidia. Eg the Mi355x vs B300 is close. The former released before Nvidia's GPU.
The same story goes back for years and years in consumer hardware too. AMD GPUs often had more raw compute capability, but fell short in actual game performance (or other applications).
Nvidia's moat is, at least partially, the software to make the hardware useful.