Because turks are really nationalistic and they see everything as a threat and they see themself always a victim. Like they see a country with a population of 10 millions provoking a country with 82 million inhabitants, just because Israel wants to link their power grid to Europe. Talking of poking and insecurity, how is it even possible to see Israel connecting their power grid to Europe as poking by Greece? Why should Greece, Cyprus and Israel ask Turkey first, if doesn't go through turkish sea and land?
I mean, the dispute between Turkey and Greece mostly is about the islands that are literally 5 to 10kms away from Turkish mainland and Greece trying to claim the whole Aegan See for themselves, citing the islands are her waters and there a LOT of islands, enough to cover Aegean See and isolating Turkey’s west shores. It causes a dispute, since if Greece would have their way, Turkey would not even be able to use her west shores.
Greece invading west Turkey in WW1 does not help either.
The conflicts are really feels like children arguing with each other. Both parties needs to stop, but I think both governments/ruling parties enjoy nationalist votes from fueling this dispute. Other countries, who have interest in this dispute, does not help either.