While US-European daytime transatlantic flights are rare, they’re at a record level. 
Delta Air Lines has only one of them: from New York JFK to SkyTeam and transatlantic joint venture partner Air France’s Paris CDG hub. The airline only started such flights in March 2024. While they were always to be summer seasonal, they have been removed from next summer’s schedules. The last day flight will leave for France on October 25.