I think the award for “riskiest dev choice” might be awarded to the developers who wrote the Boeing 737 Max anti-stall MCAS code. But it could also be argued that the root cause was hardware and lack of redundancy of sensors.

https://cnbc.com/2019/03/...

The whole aircraft concept was a hack, the software a workaround.

However, there are actually two sensors installed, it's just that the software only evaluates one of them. And then it doesn't even check for plausibility because the angle of attack on ground with considerable rolling speed should be zero.

That wasn't risky, that was blatant disregard to any regulations on how to design airworthy systems.

Even worse, there is as safety lamp, signalling sensor discrepancy. This important safety system is sold extra(!) and is optional(!).
Of course airlines are trying to as much safe money as possible, so this safety lamp is not present.