Kemoy Walker said: “My family feels happy that justice is served, although it won’t bring Prince back, we are happy to hear a good outcome.”
He said the case was a “good example of when the system works well”.
Mr Walker, a youth worker, has long campaigned in Moss Side to help support and engage young people and steer them away from knife crime.
He said he understood that many others affected by knives did not get “justice in their families, so my heart goes out to them”.
“Speaking to other youth workers, there needs to be the development of an anti-knife crime strategy that is local to Manchester and is organised by local people,” he added.
Mr Walker said there needed to be a “big conversation” about the “big crisis” of knife crime among young people
“We need to get to grips with it, it’s too much blaming the system and everyone else.”
His comments come after more than 90 weapons including knives and a machete were seized by Greater Manchester Police from schools in the region in the last academic year.