[m4rtink]

I guess in some cases lowering altitude could result in flight into terrain or possibly entering airspace where collision with other aircraft would be more likely ?

[Mawr]

Not these days, with detailed terrain maps and GPS + GPWS.

The chances of colliding with anything else would be tiny. In case of other commercial jets zero, thanks to TCAS at the least.

[duckmysick]

GPWS = ground proximity warning system

TCAS = traffic alert and collision avoidance system