In 2008, the definition of a rich pure would be having 200M and probably only 1% of pures had this much. Nowadays, it's not difficult to find pures with over 1B and I'd say probably 30% of pures have around 200M (this may be a gross overestimate, if you disagree with me feel free to comment). This is called inflation, and it happens because there is a source of money going into the economy that is larger than the amount of money leaving. Runescape has always had this problem, in the early stages of the game full rune was considered rich. As more players start playing the game and getting gold out of it, theres more money floating around. Jagex compensated this by releasing new skills or making updates to expensive skills. Construction is a prime example of a skill that just soaks up money for little return. And with the overload, summoning, and curses updates, it is pretty obvious that they are trying to remove money from the game. Every player with overloads took ~200-300M out of the economy; the same is true for every turmoiler or high summoner. I only mentioned prayer, herblore, and summoning because those three skills along with fm and construction are the ones where it is essentially impossible to make money off of.
Unfortunately though, releasing those skills actually increased the rate of inflation for the economy. Each of those updates increased the need for cash, which was easily solved by the newly (as of 2009ish) improved bots and gold selling website. These bots had an enormous impact on the economy. Even if they were purchased legitimately all it costed was ~$10 to make 10M every single day. And if you did not want to risk botting on your account, the gold selling websites would be able to give you botted money for an all time rs low. With an increased need for rs gold, there was an increased demand for gold farmers of rs bot coders. Once free trade was re-implemented, buying/transferring gold was made so much easier. With free trade came the re-emergence of staking which allowed some players to bring in more money by a single player than ever before in rs. My favorite example of this is Win All Day, who could easily get 1,000,000,000,000GP. If you assume he can sell his gold at $0.50/Mill he could easily get over $200,000.
Another unfortunate backfire of Jagex's attempts to stop the inflation is what happened with the overload, summoning, curses updates. Each of these updates made killing monsters and getting money faster. Godwars, Tormented Demons, Corp, and now Nex were made much easier and more rewarding by each of these updates. Gold farming companies kill Nex on maxed mains to farm their gold. But I'm not saying Jagex should not have introduced these updates. The game needs to progress to keep its appeal and difficulty and attract new players. I'm saying that they could have done other things, like make the items untradeable or something else.
What concerns me is that not only will the inflation increase, but that the rate of inflation will increase. Aka, a graph of money over time would have positive curvature. Besides the obvious reason for concern (there being more money). This also will increase the distance between the rich people and the poor people. I believe this will lower the interest for new players to start playing rs, which will decrease the amount of players.
So yeah, just putting my thoughts down for discussion because I was bored woodcutting. Got 90k xp writing this. Agree/disagree/predict the future.