Rich people will say, money doesn't matter. But they haven't experienced actually not having it. It's ironic.

Attractive people say, looks don't matter, but they've always had good looks. It's ironic.

The joke plays on the way deleted comments on Reddit show up as removed by deleted user, sounding similar to the earlier ironies: Deleted says deleted. Since that last is effectively meaningless, and entirely different underneath from the reaction-to-judgement underlying the first two, it's also humour from the non-sequitur.

So it turns a frustration with rich and attractive people telling us not to worry about money and looks, into a surreal joke comparing the pattern to deleted Reddit comments.