19 year old telling me it’s time to retire.

I just had a 19 year old, almost 20, ask me my age (30) at work and then she told me that I’m close to retirement and it’s time to retire..

She turned to our 27 year old colleague and told her she’s basically 30 and old now too.

I’m not offended at all, she said she wasn’t joking either, but it does really annoy me because what’s the need in saying it?