Unemployment peaked in 1933 at about 25%. Currently, it is close to 15%, but if we drop the outlier of a virus -- assuming things will return to normal -- it was just recently around 3.5% and has been dropping drastically since 2010[0]. Yet, I think many will say that things haven't really gotten better since then, right? I think we'd say the problem has been growing.
So we have to conclude that a lack of jobs isn't the answer. Conversely, underemployment is fairly high at 12-13%[1]. It is higher for young people and even rising[2]. The lack of good jobs seems to be at least part of the issue. So I don't understand how WPA solves the issue. If people are paid market wages, sure, we can tackle that 3.5%, but is that even what we want? Fed says that the current rate is pretty normal and too low can cause inflation [3].
I'm not saying we don't have a crumbling infrastructure that needs to be fixed. I'm happy to support projects and make this country better. But I'm not sure how a jobs program fixes the problem. Because the problem doesn't seem to be a lack of jobs or unemployment (again, we're ignoring the current crisis on the premise of this being temporary). The problem is that productivity has increased[4] and wages are stagnant for most Americans[5].
I'm not sure UBI is the answer either, but I'm not convinced that WPA is either. Frankly, this isn't the Great Depression.
[0] https://www.statista.com/statistics/205240/us-underemploymen...
[1] https://tradingeconomics.com/united-states/unemployment-rate
[2] https://www.forbes.com/sites/payout/2017/07/21/the-underempl...
[3] https://www.federalreserve.gov/faqs/economy_14424.html
[4] https://tradingeconomics.com/united-states/productivity
[5] https://www.pewresearch.org/fact-tank/2018/08/07/for-most-us...