You are overstating the effects of the new tax on your own players. Because you have only 7 recent sales, your tax rate for players that you acquired this week has increased only from 20 to 21 percent. For all players that you have had for more than a week, the tax rate is exactly the same as it was before the changes. You will not see significant increases until you have made many more sales.
I start selling player last week before the system announce!!!