I have a thought that it may be helpful to coronavirus as there is deficiency of oxygen level in body, so oxygenated water have more helpful for recovery and lesser the complication.
The amount of oxygen absorbed by the lungs of a human is about 11 ml/min (PMID: 9066318). Oxygen weighs 1.4 mg/ml, therefore the lungs take in about 11 x 1.4 mg = 15.4 mg oxygen in a minute. The solubility of oxygen in water is 40 mg/L at 25C, so 1 litre of water saturated with oxygen would provide the body for enough oxygen for 40/15.4 = 2.6 minutes. So oxygenated water would not be helpful in patients.