I think the biggest no-nos on this hack would be that it'd need to be certified and since it fundamentally changes the UI for the pilots, everyone would need to be retrained.

The hack itself would be a small detail line on the overall budget for the changes.

The retraining would barely be a concern. It would be a new input similar (but not identical) to the stick shaker, or a new audio alert (as was literally introduced for the dual-input issue after AF447).

The hack is the entirety of the cost, it would require completely redesigning the side-stick, updating their entire maintenance procedure (currently side-stick can trivially be unscrewed and swapped out), as well as redesigning the cabin cell to provide routing for the cables such that they keep tension and don't get damaged.

Stick manufacturers have been working on active sticks for more than two decades, and they're getting released right now. While force feedback on PC joysticks was introduced in 1997.