Sadly that niche market isn't quite what it seems.
For example, nhs actually fund (subsidise) people to fly to the mainland for appointments in Truro, and return them, they fly staff too and from st Mary's for clinics, they charter aircraft to bring over anyone who might need a chartered aircraft due too mobility etc.
Yes during summer the route relies on tourists to maintain flights but year round the need is there for the route as without it routine healthcare isn't possible.
cs