I only know this phenomenon from the punk scene and I think it still exists today. NOFX released a song about it 10 years ago.

First verse lyrics:

She asked me if I was a singer, then called me has-been
She said she really liked my band in the early '90s, oh yeah
I said stop saying those mean things, my ego is so fragile
And then she called me a poseur punk
Why don’t I drink up and get the hell out
'Cause I’m a sellout

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