Well, I agree that agreement is hard to tease out of forum discussions. But all you really have to do is to pay attention to the mountain of published facts:
1) Here is Nobel Prize winner William Sharpe's original 1991 paper where he explains why active management will always lose to passive by the difference in fees:
https://web.stanford.edu/~wfsharpe/art/active/active.htm The paper is only three pages and is an easy read. The only math required is an understanding of addition and subtraction.
2) Here is a Kenneth French video explaining Sharpe's paper:
https://famafrench.dimensional.com/videos/is-this-a-good-time-for-active-investing.aspx
3) If you don't like economists, here is empirical research from S&P:
Thought Leadership - Research - S&P Dow Jones Indices The SPIVA Report Card shows you how badly active managers miss beating their benchmarks and the Manager Persistence Report Card shows you that it is impossible to identify successful managers except in the rear-view mirror. These two reports have been published biannually for a number of years with exactly the same conclusions every time. Only the percentages vary a little bit.
4) Here is French again, explaining how he and Nobel Prize winner Eugene Fama tried and failed to find a way to identify successful managers ahead of time.
https://famafrench.dimensional.com/videos/identifying-superior-managers.aspx Their paper on this subject was published in the early 2000s. It's about 40 pages and for me a very tough read, but Google can find it for you.
5) A couple of weeks ago the WSJ published a persistence analysis of (IIRC) 1500 managers based on using Morningstar's "star" rating system and found the same thing S&P has consistently found: Success is simply a matter of luck and cannot be predicted. This article is unfortunately behnd the WSJ paywall, but you might be able to find it in the wild of you are lucky. "[FONT="]The Morningstar mirage: What those fund ratings really mean" 10/25/17
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Of funds awarded a coveted five-star overall rating, only 12% did well enough over the next five years to earn a top rating for that period; 10% performed so poorly they were branded with a rock-bottom one-star rating."
6) Morningstar itself just published an analysis very similar to the S&P SPIVA reports: "Morningstar’s Active/Passive Barometer Mid-Year 2017" It came to basically the same conclusions as the S&P SPIVA report cards: active management is a losing strategy.
"In general, actively managed funds have failed to survive and beat their benchmarks, especially over longer time horizons." There is some interesting data on fund failure rates, too.
7) Books that explain this can be a list as long as your arm. Among the most famous are "A Random Walk Down Wall Street," "Winning the Losers' Game," and anything by William Bernstein.
There are valid excuses, though, for believing that the issue is not settled. According to the BLS, there are about 400,000 investment sales people in the US (presumably including FAs). The salaries of the vast majority of these people depend on selling the myth that stock picking works. So they are out there doing that. Same story with web sites that rely on advertising, like Motley Fool. Same story with the major invstment companies. Morgan Stanley just reported 3Q17 results with their "Wealth Managment" unit pulling in over $4Billion -- all based on people believing the myth. But in all the advertising, all the op-eds, and all the newsletters there is one thing you will NEVER find: Statistical evidence that stock picking works. Because there is none. But if you like anecdotes you will love the myth-sellers. They have anecdotes by the ton. Stock prices are noisy; it is inevitable that every day some stock pickers will get lucky. But that simply masks the fact that on average it is a losing strategy.
I think of this myth-selling as similar to the chaff and flares that a military airplane dispenses when it is under attack by an inbound missile. Desperate attempts to mislead, nothing more.
Finally, all of this data is based on "passive" investing. IOW buying the broad market. IMO the word "indexing" gets used as an equivalent to passive but that is not always true. For example, buying SPY is usually thought of as "indexing" but in fact it is a sector bet. SPY will, statistically, beat actively-managed US large cap stock pickers but is irrelevant to stock pickers working the EAFE. Fama says
"We have to hold the market portfolio." IOW, everything.
Finally, here is a very worthwhile way to spend a half hour:
https://www.top1000funds.com/featured-homepage-posts/2015/12/11/investors-from-the-moon-fama/