i'm not agreeing with you. my point is that if your expecting AMs to be superstars then you don't understand what they are there for. clients get what they asked for. i don't understand your point about salesman...thats something else.
again, most people who work in AMs are highly qualified (no AM in the UK will hire you if you don't have at least a 2:1 from a Russell Group Uni, even then its still very difficult and most firms will mainly take just Oxbridge, and then you have to pass the IMC and CFA or you get fired) but that doesn't mean you make money.
your misunderstanding the rules of the game, AMs follow what their clients want which is benchmarking, short term performance and small niche mandates which (when combined with clients bad timing) leads, inevitably, to poor performance. all decent strategies have multi-year periods of underperformance but clients want more than this and so AMs, knowingly, adopt worse strategies to try and get lucky because if you underperform for more than one year you lose your job. if you think people who work at AMs don't know this, then your mistaken. unsuprisingly, most of them are very worried that they can get fired for what is essentially part of the "game".