Antoine Semenyo's stunning backheel flick on 72 minutes was the difference, giving Manchester City a 1-0 victory and a second domestic trophy of the season. Chelsea had chances to level through Moises Caicedo and Enzo Fernandez after the goal, but neither could find the finish the moment required.
McFarlane offered congratulations to City before reflecting on what he felt was a closely contested final.
"I thought it was an evenly matched game. Both teams had moments of control. Both teams had momentum at different times. Two really good sides."
He was clear that the margin of the defeat offered little comfort, but that the performance deserved recognition.
"I felt we went toe-to-toe with one of the best teams in the world and I thought there was very little between the sides. I thought we had momentum at the end of the first half, I thought we had momentum at the start of the second half. If you get that moment of quality and you get yourself in front, it makes the game very different, and we didn't manage to do that."
The result extended a run of competitive performances under McFarlane's temporary stewardship. Chelsea drew 1-1 with league champions Liverpool at Anfield days before the final, before pushing City all the way to Wembley.
The interim manager pointed to those two results as evidence of what this Chelsea group can produce at their best, while acknowledging that consistency has been the missing element across the wider season.
"We know what this team's capable of. They need to produce that on a more consistent basis. They've shown this year that when they're at their best, they're a very difficult side to play against."
He was equally emphatic in defending the spirit shown by the squad in both matches, dismissing suggestions that character has been a question mark this season.
"The fight and heart has been questioned at times, but the last two performances, I don't think you can question that. I think they gave everything today to try and win that trophy for the club."
Chelsea's starting eleven at Wembley had the youngest average age of any FA Cup final line-up since Nottingham Forest in 1991. The appointment of a permanent manager, with Xabi Alonso among those linked, is expected to be confirmed before next season.