Aside from the absurdity of this claim, consider how many years of experience a "senior" is typically expected to have, and then consider how long even ChatGPT has been available to the public, never mind SOTA coding agents.
> consider how many years of experience a "senior" is typically expected to have
That entirely depends on what the experience is towards. If it is something like farming where you only get to experience a different scenario once per year due to worldly constraints, then one would expect many years — decades, even — before considering someone "senior".
But when the domain allows experiencing a new scenario every handful of milliseconds, you can shorten that tremendously. In that case, a couple of years is more than enough time to become a "senior" even with only a modicum of attention given to it. If you haven't "seen it all" after a couple of years in that kind of environment, you're never going to become "senior" as you are hardly engaging with it at all.
Aside from the absurdity of this claim, consider how many years of experience a "senior" is typically expected to have, and then consider how long even ChatGPT has been available to the public, never mind SOTA coding agents.