If you think about it. It should not be a surprise. Large bull BG inhibit smaller BGs from breeding & taking the best spawning areas. Large males will accept a small female if she is ready to spawn. The bigger fish are most likely to pass on the best genes. If there are no big fish, then survival of the species takes over & the little guys get their chance.
At best they may be able to keep the SMB at bay giving the trout a better chance & perhaps over MANY years get the SMB under control. Yes , till some really smart angler that knows everything bucket stocks the lake again.