We do discuss the pax profile in the briefing. The CSM will usually note if there are any Prem, GGL or Guests of BA. On a flight where there are just a few Golds they may run through these too.
On a flight where there are a high number of Gold passengers, though, they may just make us aware of numbers rather than run down the list. It’ll be up to Galley Operators/CSLs to establish where in the cabin they are. In most pre-flight briefings there simply isn’t time to ensure you’re fully covering everything from an SEP perspective and then list names and CIVs of 20+ Gold Card Holders.
This doesn’t excuse the service the OP received, though, and it’s good to hear that it was raised with the CSD.