"The problem, however, is that this claim implicitly assumes that investing in complex portfolio allocations, active managers, and alternative asset classes will benefit clients in aggregate. What if the opposite is true? What if these strategies actually destroy value? Would investment consultants tell their clients?"

Yes ! A solution involves making investment managers directly accountable for the returns they expect, quarter to quarter while managing funds.
Refer to linked SEC Comment file post.

https://www.sec.gov/comments/265-28/26528-20157860-326004.pdf