Reliability is important, but complex systems also fail in complex (and unpredictable) ways.
All systems run in degraded modes, and this means failures can be difficult to predict. Therefore, adaptability is key for dealing with unexpected events. Adaptability supports resilience. Both reliability and resilience are needed for ever increasing speed and scale.
Failure Is Inevitable, Let’s Not Pretend Otherwise, by Laura Maguire.
The author of the paper focuses on distributed software systems, but there are of course many complex systems you encounter or interact with in daily life. They all benefit from resilience, not just reliability.