[usaar333]

Right and the "flu iir = covid iir" hypothesis would still lead to the real world pandemic being far worse (that's pretty obvious to anyone). You still have a disease with no vaccine that transmits extremely fast.

What would change though if that were true is that the calculus could shift away from locking down (SIP) to limited social distancing measures (to reduce r0) and a complete isolation of your most vulnerable populations. Basically, go for some sort of herd immunity if you can keep the herd's IIR below 0.01% or so.