Most people get an answer very specific to them and their cabinet. For the majority, it lets them know, in no uncertain terms, where they stand.
Those whose cabinets are commercially unviable may feel that the answer is bland, and without specific details - which is probably because it doesn't tell them specifically why their cabinet isn't viable, just that it isn't.
Where BT has determined that the cabinet is unviable, you will remain in limbo - but not because this email contains insufficient details. It will be because the BDUK plans aren't sufficiently advanced to know whether your exchange will be covered and whether your cabinet will be covered, and whether your line will be covered.
I understand that being in this position will remain frustrating. But you *will* know that you are in this position. (*)
BDUK: Central governement has made a pot of money available to improve broadband in the UK. The central target is to get coverage of "superfast broadband" (>25Mbps) up from BT's commercial coverage (of 67%) to 90%. It has a fallback target to ensure that everyone else gets a minimum of 2Mbps.
The funds are allocated to (mostly) county councils, at level relative to how rural they are. The onus is on each council to determine how to go about the programme, what extra money to add to the central pot, and whether to apply for additional EU funds.
When the councils select a commercial partner (all signed contracts have so far plumped for BT), they move into a detailed planning phase. There are a lot of counties at this stage - only one county has advanced far enough to actually get cabinets on the ground.
Most counties seem to be going for a large percentage of FTTC coverage, but almost no county has yet gone far enough to be able to detail coverage down to individual cabinet level.
Hence, if you are on a cabinet that isn't viable in the commercial rollout, you won't yet know what the status is on the BDUK rollout, whatever county you are in.
First step is to enquire at Openreach. If they tell you that it is unviable, you go to the second step of finding out the BDUK status locally.
(*) - BT do muddy this slightly by occasionally changing the status of a cabinet. This happens, but sufficiently rarely for you to not consider it for now.