People have no idea how little excess capacity there is in ICUs anywhere. We have about 100 k ICU beds in the US and they are swamped during flu season. Patients routinely held in the ER waiting for a bed.
Waiting room full, every room full and people on beds and chairs in the halls. I have seen it nearly every flu season. Ambulances on divert to another hospital that isn’t full, not that such a thing exists.