I like RAs work, and I use it as a vague guidance.
There are reasons why, for example, Europe is cheap, but my thinking is, it's been relevant for centuries, I would bet it will continue to be regardless of the momentary issues.
It's funny how consistently the same people that manage to handle their finances better than 99% of the rest of the population are dogmatically sure nobody can beat the market.
The market does a lot of stupid things that can be avoided, it overreacts to quarterly earnings, it is prone to excessive enthusiasm and panic, it trades way too much, etc.
I have 50% of what I save automatically go into index investing, because I think it's good and healthy, but the rest I manage personally.
I don't have a bar to measure myself against prior to 2013 (I'm from Italy and indexing is still unknown to this day, as it is in most of Europe), but I've done much better than the S&P500 since then.
Mostly luck maybe