what i'm going to do is making an adequat guess:
You have a valid point that the people who hoarded to much are dumping there surplus of cash. That cash goes into the less fortunate teams who upgrade arena's, buy new prospects or get a new staffmember. Considering that prices for staffmembers have also sky rocketed, the extra cash that is in circulation also goes there.
As for your longterm effect, it will take a while to die down. the super amount of cash for a trained player from for instance a IV or III team, will probably be invested in 2 or 3 others players to upgrade that squad. Say, he's got 3M for his super talent, and invested it in 3x 1M player, then the 3M from the original team hoarding guy goes down to 1 different teams. Those teams could then upgrade there roster aswell (or staff, arena, scouting, ...) meaning that in the longhaul, the cash will be redistributed over the other teams. Ofcourse, the team who got 3M could decide to hoard it aswell for a little while.
There are different scenario's, but all in all the prices will go down once all that surplus hoarded cash has been distribuated over a larger amount of teams by reinvesting and upgrading those rosters.
As i mentioned, it won't go to the original price you had a couple of seasons ago. but it will still likely go down from what it is now (this estimated guess is based upon the logical principles of economics. that doesn't mean you'll see marked improvements, it's something that happens slowely ;)