Are kubernetes namespaces this well isolated? I wasn't aware it was at the point where you could put untrusted tenants next to each other in the same cluster.
You can achieve good isolation with a combination of RBAC, network policies, OPA rules and runtimes like gvisor. We also monitor suspicious activity with Falco.
For deeper security, we offer Okteto Teams, which runs on a dedicated cluster, and Okteto Enterprise, which runs on your own cluster.