True, but many of the students will be younger than many of the retired nurses that are being urged to re-enter the workforce and will perhaps have a better immune system if it comes down to limited PPE. Since this is an infectious situation the lack of staff will only get worse and many of the skill and experienced nurses may get sick and possibly die (worst case). Then you may have a situation where limited experienced nurses are available for the workforce and to train new nurses (however limited it maybe).
Once again, this is preparing for the worst case situation. Everything might get better soon. Just throwing options out there, everyone makes up their own decision. Either way I hope everyone can and will stay as safe as possible.