Until need to debug an issue and you're way over your head due to all the moving pieces.
It’s not that hard to debug issues in kubernetes. Check status of pods, memory levels, storage mounts, network configurations, and the stacktrace you’re debugging. Not that difficult.
I’m not saying there aren’t edge cases, but if you set up your system with centralized logging (filebeat) and have some way to scrape metrics (jmx, built in tooling) you’ll be fine.