If you say "I never worked with X, but I learn fast", with your best sincerity at the interview, then you're automatically out of the process.
Where X can be not just k8s but any other bullet point on the job req.
It's interesting that the very things that people used to say to get the job 20 years ago -- and not as a plattitude (it's a perfectly reasonable and intelligent thing to say, and in a rational world, exactly what one would hope to hear from a candidate) -- are now considered as red flags that immediately disqualify one for the job.
Very sorry to hear about your current situation - best of luck.
Ive never heard of this - has this been your direct experience?
It's somewhat speculative (because no one ever tells you the reason for dropping your application or not contacting you in the first place) but the impression I have, echoed by what many others seem to be saying, is that the process has shifted greatly from "Is this a strong, reliable, motivated person?" (with toolchain overlap being mostly gravy) to "Do they have 5-8 recent years of X, Y and Z?".
As if years of doing anything is a reliable predictor of anything, or can even be effectively measured.