Yes, IME that's very close to the truth. I think that's the “less strong version” of this comment that people were talking of.

The Blueprint Decoded puts it as ‘when you [feel low-status], you don't give yourself permission to [do high-status stuff]’.

(I also seem to recall phonetician John C. Wells claiming that it's not like working-class people don't know what upper-class people speak like, it's just that they don't want to speak like that because it'd sound too posh for them.)