It is not all the time that luck plays a role when you compete with people that are equally skilled. Sometimes, one person just works harder or smarter than the other or has more resources than the other. Luck plays a role but its not everytime.
I agree with him to an extent because of the point he emphasised.
As people become more skillful, luck becomes more important. That’s precisely what happens in the world of investing. In the short term, you may experience good or bad luck [and that can overwhelm skill], but in the long term luck tends to even out and skill determines results.
Luck works more like that in the short term. When two people competing are equally skilled, one might be luckier than the other and win, but that won't be able to sustain that person for the long term. In the long term, skill is what sustains you.
In football, a team can get lucky to win a match, but its skill that they need to be at the top for a long time. From time to time, they may get lucky or unlucky, but if they don't have the skill, in the long term, they wont win much.