There are lots of cities in Europe that are far easier to access from Frankfurt than Schiphol. The 11 hour gap between the EI841 and EI 845 makes the latter unattractive for many connections particularly when returning to Cork. Some would argue that a 3 hour bus journey from Dublin is more attractive than an 8 or 9 hour layover in Schiphol.
In general the ratio of short haul flights between Dublin and Cork should broadly reflect the population difference between their various catchment areas but that clearly isn't happening on many routes. Cork should also try and re establish it's links to some of the UK provincial cities such as Southampton, Exeter, Leeds, Cardiff and Durham. It's incredible that we were able to support a viable Cardiff service 50 years ago and we can't get one today when air traffic has increased by about 25 fold since those early days.