I think this achievement is probably never going to be earned anymore. I think the only people who will ever earn it have already done so, back in the era when there was no salary floors, player salaries were lower but revenues were still the same, and so it was a lot easier for managers to earn lots of money, thus raising the overall price of players on the TL as everyone had money to burn.
Put it this way: the most valuable players in this game are well-rounded SFs and PFs, since they require every skill, meaning a lot of out-of-position training for a long time. They are incredibly cost-efficient and versatile though, which makes them very valuable to have. One of the best of these that I've ever seen, Robby Serrano
(20740069), sold for $5.6 million. This is a guy who was a U21 player, had 120+ skill points at the age of 23 (which is pretty incredible, I've never seen another player with more skill points at that age), is a virtual lock for the NT for the next several seasons if kept in decent game shape, and is still only 25 years old making him very trainable. He could easily reach that 140 TSP mark and become one of the greatest SFs in this game. And he's USA, and USA players tend to sell for slightly more than their comparable foreign counterparts for some reason, possibly because buyers have visions of the RL NBA in their heads when they think about buying USA players. Bottom line: If that kind of player sells for "only" $5.6 million, I can't imagine any player worth $10 million in today's BB economy.