I think it’s because software engineers are shittier than their hardware counterparts of yesterday. And many of the problems we see are to do with software or the sw/hw interfacing. Despite the significantly easier ability to test software than hardware.
Although I think hardware might be a more deterministic in terms of possible states to consider and test for whole software has states of the application as well as hardware and the effects of other concurrent applications.

But definitely your observation could be due to this migration to a thicker software layer (multiple layers, in fact)