What did the experts get wrong? If anything this pandemic was more political than scientific in many cases.
Rroff covered many of them but also it's only really this thread that keeps popping up that keeps me in touch with COVID for over 3 years as it's not been an issue for me or people generally bar the minority that we hear about in examples in this thread.
For the record I'm not pooh-poohing yours or other people's lived experiences but this thread is atypical to that of what I see to be the majority globally (admittedly it's only via travel and discussions rather than reading the local news of those countries).
I'm trying to do this from what I remember and I don't disagree a lot of it was political posturing.
So... The Initial view assumed it would behave like SARS1 (droplets, severe for most). The shift in Evidence showed very different spread and outcomes. Now: Distinct virus, airborne, superspreading, uneven severity.
On Transmission the nitial view was droplet and surface spread with mass disinfection emphasised. The shiftbbased on outbreak studies proved airborne transmission was dominant. Now it seems that aerosols are the main route, surfaces play a minor role.
On the Risk profile initially expected severe illness for most, based on Wuhan/Italy cases. But the data showed majority had mild cases, c10 to 15% at real risk. Now it seems that the risk is uneven. elderly, comorbid, immunocompromised, and some with genetic susceptibility which is what I've been saying in this thread but often rejected for this opinion.
Variants a favourite topic here!
The initial view and guidance continued based on original Wuhan strain. But the shift from Alpha, Delta, then Omicron changed transmissibility and severity. Now the Omicron family is dominant, faster incubation, milder per case, strong immune escape.
The Incubation & isolation advice was based on 14 day isolation, copied from SARS 1. But it shifted as the data showed c. 5 day incubation, then c. 3 days with Omicron. What is happening now is more Symptom-based isolation (stay home while sick, not fixed days), which let's face it is sensible. People should have been at home back when sick for decades but politics and work pressures...
Initial view on testing was that PCR was seen as gold standard, single test enough. Then we moved onto antigen tests shown to track contagiousness; repeat testing needed. Now it seems that PCR best for diagnosis, antigen best for infectiousness (serial use). Though let's face it most people haven't done a test in a couple of years now if not longer.
There was a lot of fuss over treatments and many so called experts saying stuff like chloroquine, broad antivirals, and many unproven drugs (can't remember their names).
But the shift happened when random controlled trials showed most were ineffective but dexamethasone (?) and Paxlovid showed benefit.
I believe Antivirals are now being used early for high-risk patients and immune modulators for severe hospitalised cases. I don't know exactly how those work, but my medical friends explained it a while back but can't remember it enough!
And the ever "political element" Vaccines!!
The messaging suggested they would stop infection and transmission. But we knew that real-world data showed breakthrough infections were common, but still good against severe disease especially for those with comorbidities or immunocompromised people and the elderly. We now know that the vaccines reduce hospitalisation and death (in particular vulnerable groups) only partial and temporary protection against infection.
There's no damning thing here but it shows how over a short period of time expertise changed as knowledge increased. Nothing new here this is very normal in scientific environments.
But again politics created a lot of misinformation and sensationalising by media and social media.
can't be a nice way to live. 
