That's not filthy rich, that's slightly grubby rich
well, I have way more money than I need, and I even get more every time I play (and even when I don't play, if I could be bothered to invest the time to make money with my carrier). I could crash my most expensive ship hundred times in a row and it would be the same, still way more money than I can use. I could buy everything for my carrier (only bought the parts that help me or others for now, no sense buying cartographic data in the bubble, fence stolen goods or take in bounties). I pay 20M every week for the upkeep, plus a few dozen millions for tritium. I can and do give away hundreds of tons of rare goods to strangers, donate millions to various factions to support them in their BGS struggle, and still the money only goes up.
It doesn't matter if you have 1 billion, 10 billions or 100 billions, when you got the ship you prefer you are rich. And if you keep that space-dust you'll soon be filthy too.