Of course Hollywood screws up firearms, but I've already discussed that elsewhere, let's talk about how Hollywood screws up elevators.
First off, elevator doors aren't bulletproof.
Every time you've seen a spy with clips and boxes in elevators "haxoring the boxor" is complete nonsense too, as subverting elevator security is easier than you might think, and the elevator industry is way behind the times when it comes to security. In the movie 3000 Miles to Graceland, the dude is hacking the elevator box and is clipping his alligator clips on a timing crystal and a capacitor on the elevator's emergency phone, and somehow he subverts the elevator security and causes the elevator to behave in a way that's outside of the norm, which is Independent Service Mode in a nutshell, which you just need a key for that.
Apparently in Die Hard 2, the access to the top of the elevator is never locked, because why would you want to bar access to the elevator controls that override even firefighter security, VIP access, and such you filthy animal? Of course, there's nothing in the elevator's hoistway that's dangerous, like the massive counterweight that weighs more than the elevator's cab and occupants!