surely Cork Airport could offer exclusive rights to one airline for a fixed period thus ensuring some stability for the long suffering flyer
Any airline from an EU member state can operate a route between any airports in EU (PSO routes excluded, blacklisted airlines excluded). You could have, for example, 20 airlines operating Cork to Birmingham and neither Cork Airport, The Dublin Airport Authority, The Irish Aviation Authority, The Civil Aviation Authority, nor Birmingham Airport could do nothing about it as long as there were slots enough.