These are only results of the US-specific lack of welfare protection mechanisms, not a lockdown per se - especially unememployment and to a lesser degree also the negative growth are significantly less accentuated in the other OECD countries.
The high unemployment was because of how the US structured the spring legislative response. Businesses were ordered to close, and that made employees eligible to collect unemployment insurance. A federal program paid those unemployed people $2400 a month (in addition to their unemployment insurance).
The US poverty rate went down during the period. So it wasn't a lack of welfare protection, it was just a (likely bad) implementation choice, paying individuals instead of paying businesses to keep them on payroll.
The lack of response since that expired in July fits your description though.
I know, I'm not from the US but I tried to follow the US development closely. Many other countries have furlough-like systems where workers get money in cases of force majeure like floods or a factory burning down, without losing employment. One usually gets payout as a percentage of regular wage (depends on the countries, I'd say it usually lies between 60 and 90% of net income). These institutions were already in place, and when lockdowns were ordered the government just had to inject more money into them. All the red tape and all logistics were already in place. Most countries also allow soft fade-outs (I'm lacking the proper word here, sorry), i.e. 80% furlough and 20% regular work in month 1, 50/50 in month 2 etc.
The big advantage of this approach (in addition to the obvious advantages for the workers) is that companies don't lose the organizational knowledge held by the workers: With whom to speak in case machine X fails, whom to approach in customer company Y for a new deal etc.).
