Garcia, Westwood and Poulter were absent from Europe's victory over the US at the Marco Simone Golf & Country Club after resigning their DP World Tour memberships following their decision to join the Saudi-backed LIV circuit.
The trio had played key roles at the Ryder Cup over the years.
Garcia is Europe's record points scorer with 28-1/2 from 10 appearances while Westwood earned 24 points in 11 appearances at the biennial event, finishing on the winning side seven times.
Poulter played at seven Ryder Cups and helped Europe win five of them, with his huge performances earning him the nickname 'The Postman' as he always delivered at the event.
"They've had unbelievable Ryder Cup careers and they've made their choices, and they've done what they've done and no one can take away the impact they've had for the European team over the years," McIlroy said.
"But I feel like this week, not having those big personalities in the team room let other guys have that chance to flourish and to shine: Viktor (Hovland), Jon (Rahm), myself.
"There wasn't a ton of space taken up in that room by some of the other big personalities, and I think that just let the rest of the team just sort of flourish. It's a young team. We can all grow together.
"I could potentially be the oldest person on the team next time. It's a new era. And it's a pretty good one."
Shane Lowry agreed that the victory in Rome could be the start of a new era as they shift their focus to the 2025 event at Bethpage, New York.
"I think so and I am not even talking about the 12 players who are here. I am talking about Rasmus Hojgaard, Vincent Norrman and Adrian Meronk," Lowry said.
"Look at all the young players in Europe coming up, we have a great foundation now for the future and I think it is a great chance to look forward."
