It used to be 95% failed at trading, now it's 99% and soon it will be 99.9%, they can't handle the volatility as everything is moving to fat-tail events, lots of flat and then rapid spikes. The people who make the money are those selling the services, seminars, books, and managing funds.
It's very simple, to trade like a pro you have a very small margin of error, 1% wrong and you get nothing. The service providers and fund managers only have to prove a 1% or 5% gain and people will buy it like hot cakes, it feeds their greed, everyone wants growth. Most get negative returns but the providers dilute that by saying it was a bad year or it was your mistake not doing it properly, then the next year is the same and so on, dilution is the greatest myth of life.
So made +19% of account last month on one trade, it's via via a fund who specialize in these high value trades. These forums as you say are not necessarily angry people, but people think that a 1% or 5% gain is being successful, they're delusional but that's not necessarily their fault. So when someone comes along with 8% that will set them off, or when they are negative because the 5% method they bought is useless, they will not be impressed.
It's cheap to lie, a lot of people want other people to feel useless to match their own situation, unfortunately it normally works. The trick is to ignore them, never respond to replies, actually don't even read them, 99% of the time it is some idiot who wants to pretend their 5% actually means something intelligent.