Once you understand how a mechanical ventilator works for ARDS patients, you'll realize that snorkel masks and CPAP machines ain't gonna cut it. They might make it more comfortable to breath for a while, but when breathing gets critical in a patient, those alternative devices are probably not going to save lives. This is my VERY
uninformed opinion, but I HAVE watched a youtube video about how the
real ventilators work, and it's not just simply pushing oxygen or air into a person's lungs.
When treating ARDS, the patient is usually "out cold", otherwise the patient would "freak out" because the urge to breath by one's self is hampered by the machine.
If you want to learn about mechanical ventilation, here's a youtube link. I've got it queued-up at 2:18, which is the start of the intro to mechanical ventilation:
https://youtu.be/mnIpD1VwyMo?t=138
This is from another of this doctor's videos: