Option #3:
COV2 has receded to non-dominant levels and we're seeing essentially normal waves of other respiratory pathogens, in some places with overascertainment from COVID-era hypertesting and panic-driven care-seeking.
This would explain why pos% peaks are normal.
The recent surges of respiratory viruses have been blamed on 2 causes:
1. Reduced circulation of bugs during the pandemic having led to lower population immunisation ('immunity debt')
2. Covid infection causing some form of immunosuppression ('airborne HIV')
1/