1)I'm no mathematician or statistician, but as I understand it the IFR also counts an estimate of those presumed to have had an asymptomatic case. A published study earlier this month estimates that the reported number of non-hospitalized cases between February and September of 2020 accounts for 1 out of every 7 cases of reported infection because of reasons like the symptoms weren't typical or didn't appear at all, amongst others. I don't know if that puts the IFR as low as they are saying, but it's still pretty low.
https://academic.oup.com/cid/article/72/12/e1010/6000389
2) The lockdowns have not shown any statistical data to the effect of controlling the transmission of the disease. As an aside, they actually have some support that they may have created a negative impact overall as people were forced to reside with family members who contracted and passed on the disease. There are plenty of anecdotal pieces of evidence on both sides of the argument on the subject of lockdowns. That in and of itself should be an indicator for caution and moderation when calling for unilateral action.
3) Even if one subscribes to the idea that the lockdowns did have a positive effect in controlling the rate of infection, the lockdowns were never billed as protecting the vulnerable. That was masking. The lockdowns were billed as an effort to stop hospitals from being overwhelmed. Sure, while there were hotspots and times of higher activity, I have not personally come across data that shows that these hospitals were ever in danger of being over-whelmed. However, I have personally seen examples of people who have lost their jobs in the medical industry because the shift to a laser focus on COVID-19 caused someone to lose their job due to lack of the necessary funding.
I don't know that any numbers are really going to add up for quite some time. I do think that the imposition of unilateral action like lockdowns was a terrible idea and the cost of doing so will continue to show itself over the next several years. Data will continue to change and be updated just like it is for all major medical events. It appears to me that perhaps the best course of action is making recommendations to people and letting them chose their own path. The history of this country and trying to impose something by force is not exactly stellar.