The Bournemouth skipper led the side which was beaten 3-2 in the final by Brentford, but they reached that stage thanks to a sensation 15-game unbeaten run – a streak of 14 wins on the bounce.
Speaking after the defeat, Kinsey told the Daily Echo of his pride in the side’s mentality to get to that stage.
“I feel like we take everything that we do off the pitch, on the training ground, onto the field here, like the culture, the character of the boys,” he said.
“We left that out there all tonight. And as captain of this group, I'm so proud of the boys.
“So proud of everything they've done, in particular, the past two, three months has been unbelievable experience.
“I feel like this game, regardless of the result, the performances we put in, leaves us all in a really good place going into next season.”
There have been a number of first team opportunities for development squad players as Andoni Iraola’s side has been struck by injuries.
_(Image: Richard Crease)_ Kinsey featured in 14 Premier League match day squads from November to February and came off the bench in the FA Cup against West Brom.
Fellow development squad players Ben Winterburn, Zaine Silcott-Duberry and Remy Rees-Dottin have all played for Iraola’s side this season, too.
Reflecting on the campaign as a whole and the impact those first team experiences had, Kinsey said: “I feel like every season has its ups and downs.
“That's natural for everyone. I'm sure Brentford have lost a lot of games as well as us, but to go 14 games unbeaten like we have to get to this stage is pretty unheard of.
“And the boys that come up and down, like I've been with the first team a little bit myself, the boys that are still up there now, there's never any ego, nothing like that coming back down.
“We're such a close-knit group that everyone fits back in.
“When you go up there, the level's so high. Obviously coming back down, you know, you might be a little bit mentally sharper, training with some quality players.
“So all those boys that come back down bring that to the group and just trying to lead the group like all of us boys, especially the older ones.
“We definitely have raised the quality of the group so far. And over the past two, three months, I feel like it's been unbelievable what we've done.”