Flybe negotiating with BFS is just another bargaining chip for dealing with BHD. BE would not work on comparable routes to easyJet ex BFS. Is FR considering major network ex BHD to rival BE, unlikely. FR coming into LGW or STN will impact BE least or any carrier on the London route. Me thinks this is unrelated.
Ryanair prefer BFS for operational reasons, earlier starts, longer days, higher aircraft utilisation, hence lower costs. FR do not care whether bhd is in the city or closer to the population etc. Price price price, cost, cost, cost... That's their game.
In relation to tourism Ireland, they could I guess support or subsidise new routes to new destinations like Germany etc. But unlikely to be the case for Gatwick etc.