I think the actual point being made about the vastly changed...

I think the actual point being made about the vastly changed treatment landscape was that early in the trial people were being put on ventilation once their condition deteriorated whereas in the latter half of this year ventilation was no longer a normal treatment but rather a last resort. So not only does this mean that enrollment was slower, but the odds of saving them was much reduced. The trial had a few restrictions but with the benefit of hindsight it should have restricted enrolment to patients within a few days of ICU admission, but had this been in place we likely would have had no enrolments. The treatment landscape just changed too much across the time of the trial.