EMTALA in the US appears to dominate among a myriad other sister regulations in this medicolegal and medical ethics problem space. The decision should be left to the staff on the ground with the details of the situation at the moment.

An unaddressed gap is medical staff on the pandemic front lines without adequate PPE are still shackled by these rules made for a system that is not overwhelmed by a pandemic. These need to be waived for the duration of the emergency.

No, but a person in an ICU bed will need a lot of other services which might be subject to triage. (Remember that "beds" is a shorthand here - it's not a shortage of physical beds that's an issue, it's easy and quick to build beds.)