Is this switching risk-free? Consider all these ancient computer devices that run high-stakes equipment for years and decades without change. An RPi could replace an ancient PDP-11, cost a fraction, consume a fraction of energy, be faster, etc. But it also may introduce new and unknown failure modes.

Yes, all stability in real life is metastability, it needs a constant effort to maintain. A worthy innovation can lower this effort, or lower the risk of a catastrophic failure.

A complete stability is death.

Resistance to change is very different than reluctance of change.