Note the missing #:configuration-file.

[0]: I don't know if this is really a bug--in fact I suspect it's 
the raison d'être of this variant--but this needs to be better 
documented and perhaps even renamed.  To me, ‘generic’ means 
‘distro default’, or perhaps ‘sanely minimal’, not ‘our own 
upstream's sometimes questionable defconfig that can't boot our 
own desktop’.

Allegedly.

Kind regards,

T G-R