I would say loss of situational awareness when some pilots understand the ATC and some don't.
Right. So what about multiple tower or ground frequencies? Military colleagues on UHF? I am still waiting for the proof that single-language ATC
is safer. What about just looking out and use common sense? Dual-language ATC airspaces have been around for a long time, where is the dreaded danger? This is usually the pet argument of monoglots.
Or maybe you are on final at around 4 nm and the guy is authorizing another traffic to cross the active runway (happened to me in Spain) and i had to go around since at minimums i just saw the guy in the middle of the runway at the first intersection moving extra slowly.
Big deal. Sounds to me you have never been to ORD. Talk to me about situational awareness when you have flown and taxied a few years out of there.