Companies often appreciate people who can change the terms of a problem and who are alert to the possibility of doing so.
I assume also your hack required some level of skill and familiarity with the system.
The real purpose of these tests is often to simply suppress the wages of a portion of the workforce, ostensibly on objective grounds (because arbitrary tests would raise people's hackles), but it doesn't much matter whether the selection is completely random. There's often little science to them.
Another reason for the use of tests is simply to filter a surfeit of applicants. Again, people sometimes like to think the filtering is objective or maximises the value of the choice, but the real baseline purpose is simply to reduce the number of candidates under consideration to a manageable number, without excessive cost or labour from those responsible for the filtering. Throwing two of every three CVs in the bin, by time order of application, would be a similar approach, but lacking the sheep's clothing of objectivity that some kind of test of knowledge or skill has.
These two purposes are often perceived by different people in an organisation. It is typically HR (perhaps through some kind of bank representative or workforce consultant) who will hitch a pay differential to the outcome of some testing process. It is the hiring manager who might devise the details of the test, for his filtering purpose. Neither needs to know what the other is about. Others will eventually just adopt these practices mimetically and without critical scrutiny, because they seem to be accepted practices in profitable businesses.
I speak, incidentally, as someone who generally does well on all sorts of tests - so much so that in most cases I'd choose to handicap myself by not cheating even if I thought I could, just to make it challenging, and for my own pride.
It's that which allows me to appreciate that the real agenda is not to reward me for the accidental inheritance of birth or variation of personality, but to undermine my willingness to be solid with the rest of the workforce and thereby enable attacks on all our wages, by convincing some they are better than the rest (and throwing them an extra bone) and convincing some they are worse (by applying a process to undermine their confidence).
That's why the veneer of objectivity makes the difference between acceptance and uproar, it must convince certain people they are deserving of a special lower wage, and convince the others that they deserve their bone.
From that perspective, why feel guilty about some old and spurious test, and whether it is fixed now?