As I understand it, the physical blind spots are getting larger in very recent model years as the car shapes keep changing. The blind spot monitors are partly a compensation for this, so you need to compare driving experience in these rather than with an older model where we easily drive without such electronic aid.

It's not clear to me how much of this change to the car shape is driven by competing safety standards, i.e. side impact and rollover protection, and how much it is the continuous march of fashion/stylistic tweaks.