I agree, never used to be a thing. I suppose it’s harder to criticise someone for disappointing you or shoddy behaviour if they claim it is down to a mental health issue rather than any other white lie.
On that Guardian piece, the thing I find odd is the presumption that Rita’s friends and family should pick up the tab when she dropped out at the last minute. She should be responsible for her own costs - and I don’t see why her having anxiety is an answer to that. I’d expect her to pay if she had dropped out because of a flat tyre / working late etc. Her attitude smacks of entitlement which seems to co-exist with the use of her “anxiety”
to guilt everyone else into paying up.