I'm tired of k8s as a hammer tool where every project looks like a nail.
It's scary to imagine how many servers are idling with zero traffic load doing nothing. Even in-house systems without any scaling ambition deployed to k8s.
Of course, you have to reserve 1 cpu + 1 gb for k8s needs on each server (you have 3 minimum) sitting here reserved, doing nothing. You can't use it for rare spikes of load (compiling, some rare data upgrades) and you have to buy additional resource to cover you needs while default resource requirements just idling because zero traffic of the system.
I'm sure it wasting more resources than all crypto-fads combined.
I'm happy to see more companies realise that and using just bare servers or docker swarm / nomad if they want to dive into DevOps and CI/CD practices.
K8s is a great tool for particular problems (you have at least tens/hundreds of servers, DevOps team more than 2 employees, you are getting at least 1k RPS at low traffic part for the day, have several SRE and so on).
Most probably your system is overengineered and resume driven if you need static k8s cluster and don't have any consumer facing interfaces (i.e. general low traffic usage pattern).
If you have different opinion I'll be happy to hear your points.