Deepest condolences, Mark
I think the lack of drivers is simply due to a lack of general interest in this type of racing (historical races). In addition, the AC players are gradually decreasing.
We have endeavored to advertise and entice new people. Mark published the calendar on the Kunos website well in advance, Tim and me have contacted other players who are passionate about classic cars who have raced with us in other groups.
There has been some results, in fact two new pilots joined us, Maxime and VVA, both great fans of old F1s and good drivers. Other pilots did the first races, but unfortunately they left, perhaps because they were not very interested and in part perhaps also because of the small chaos of the server (delayed start, etc).
From personal experience (years of air simulation) I say that if one is interested he plays, if instead he is not interested he does not. Maybe he does an event just for education, but then he will leave.
It will be increasingly difficult to have new players, because AC is aging and its playbase is slowly decreasing.
This has happened with GPL, IL2 '46, etc, and will also happen with AC. Obviously someone will stay, but it will be difficult to have new people. In general simulators have lost users.
The problems with the server have been completely solved since Fmg is in "reserve", and therefore can intervene quickly. Besides, we all know Pete's problems. The delays of the server are not, in my opinion, a cause of lack of pilots. If one is interested, play anyway.
In any case, an average of 11-12 players is not too bad.