His thesis seems broadly to be that by accepting gifts whenever they're offered, he is making the world a better place - opening himself up to kindness somehow encourages kindness in others. This is nonsense and totally backwards. What he's doing is just soaking up a whole world of goodwill and generosity, and giving basically nothing in return. "Paying it forward" is a chain - people do nice things for each other in the hope that the recipients of that goodwill will provide similar generosity to others in the future and together we make the world better for all of us. It's socialised good will - creating a rising tide that lifts all of our boats. The author of this piece has instead acted as a kind of capitalist, moving into a space with abundant resources (i.e. the generosity of others), and harvesting as much as he can, wondering at how much resource there is available for him to take, marvelling that others leave it there for him when he would likely not do the same, and patting himself on the back for taking it so that more can flow into the space.
It's somewhat akin to high frequency traders claiming that they benefit markets by providing liquidity.
Maybe we should all just follow his example, and then none of us would have anything left to give each other. Narcissistic nonsense.