I think a salary cap fixes it. Say the cap 1 million, no matter how long you tank, you can still only have a 1 million $.
Well it is something that's been suggested regularly for a long time now. Maybe worth consideration after all.
How about training exemption though? Players being trained will increase their salary and if this will lead to going over the proposed salary cap in some cases, how should that be handled?
Maybe a soft cap with x2 for the amount over the limit? This will not stop hardcore tankers though... Just make their runs shorter and tougher. It's still something.
Also I personally believe 1kk is too low for present-day BB. Something closer to 1.2kk maybe.
BBB: 2 (S37 S38); Top tier: 7 (S35 S36 S37 S38 S39 S41 S63); Cup: 9 (S25 S35 S36 S37 S38 S39 S40 S41 S61)