This looks pretty bad. Verner and coauthors pumped their research that lockdowns increased growth after 1918, huge news coverage everywhere. MIT even bought ads about it
https://almlgr.github.io/paper.pdf
Turns out, it's just pretrends. Did they not check, or were they hoping to get away with it?
Bravo to the students. I guess when there's no jobs out there to lose, don't have to worry about the job market...