2002 civic used a mechanical throttle cable and mechanical transmission linkage. These Toyotas/Lexus(s) did not use any such mechanical links to the drive train, they were dependent on software wholly.

The engine management on your parents' Honda cannot adjust the throttle percentage or gearing, only ignition and valve timing along with air/fuel ratios and gear hold-out timings. This could result in a surge of power, or a stalled car, but nothing like the experience of wide open throttle.

The Toyota UA is thought to have been rooted mostly in the fact that they adopted fly-by-wire throttle schemes while failing to compensate for the much more major software/hardware/management risks that come with such systems.