After mutual following, why doesn’t exposure necessarily increase?

Suppose Xiao Lin and A Yu mutually follow each other, and she posts an original wallet tutorial. When the boost parameter is non-zero, the source code adjusts the coefficient of the response prediction term; other predictions and filtering still affect the outcome.

《Unpacking the X Recommendation Algorithm》04
Case assumption|Public version 76843a5; online configuration may differ.

https://github.com/xai-org/x-algorithm/blob/76843a5eea278ced444b21372d4e6d6909f5c35e/xai-value-model/weights.rs#L78