Barker's side pushed Abdeslam Ouaddou's Orlando Pirates all the way in the final, with the game heading into extra-time after a 0-0 stalemate.
Pirates ultimately emerged as 3-0 winners following goals from Tshepang Moremi (92', 110') and Tshegofatso Mabasa (103').
It was the second time in two season's Stellies have succumbed to Pirates in the MTN8, after losing 3-1 in last year's final.
Speaking after the game, Barker said on IOL: "I do think lessons were learned.
"Once you get regularly into finals like we have, it's our third final in three seasons, sometimes you may not win all of them.
"But what you do gain from being in finals is we also gain our own experiences and hopefully these experiences can stand us in good stead going forward.”
Stellies have endured a slow start to their Betway Premiership with just one win and one draw, alongside three losses from their opening five games.
They are next in action away to AmaZulu at the Princess Magogo Stadium on Wednesday.
"We've got work to do in the league. We want to make sure that if we want to be in the top eight again, we need to get up as quickly as possible," Barker added.
"Get over the defeat and get back into the league matches and improve our position on the log. We're a team that has the ability to bounce back, so that's going to be key."
As the 2025/26 Betway Premiership season intensifies after the opening rounds, midweek action on September 17 at 19:30 could reshape the standings amid a tightly packed table.
Arthur Zwane says it's imperative that AmaZulu end their barren run against a wounded Stellenbosch with a win at the Princess Magogo Stadium on Tuesday.
Zimbabwe striker Thandolwenkosi Ngwenya has backed himself to score goals for AmaZulu after returning from international duty for the 2026 World Cup qualifiers.
Orlando Pirates coach Abdeslam Ouaddou has fired back at his doubters after guiding the Soweto giants to a historic fourth consecutive MTN8 title.
