For the reasons listed above, there were 3 potential outcomes, depending on the success of the public health measures to contain the spread of COVID:
1. A high number of COVID cases and a high number of flu cases.
2. A high number of COVID cases but low number of flu cases.
3. A low number of COVID cases and a low number of flu cases.
If flu and COVID were independent, there would be a fourth potential outcome (high flu cases and low COVID cases). Majromax is saying that it was largely predictable that this fourth outcome would not happen.
The thing that the news articles are warning about is outcome #1 which, if it had transpired, probably would have been quite bad. Note that the experts in the articles are warning about something that could happen, not saying that it will definitely happen. And the reason it didn't happen is at least in part due to the warnings that were issued.