This talking point of once-sky-high marginal tax rates gets a lot of airplay, but it's very misleading. Almost no one paid those rates. Tax receipts as percentage of GDP have been remarkably stable over time:
> Tax receipts as percentage of GDP have been remarkably stable over time
That may be true, but since the sources you listed contradict each other, I'm left confused. I can find supporting evidence of the graph[1], but not of the wikipedia entry. The world bank apparently thinks they are all wrong[2]. Then there's a report that Norway is actually doing it with much less taxes than Denmark and Sweden[3], but that might be likely due to oil revenue. I'm left to conlcude that without a lot of research to look into the specifics, there's quite a few ways to measure this, and I'm not sure which are most relevant to the discussion at hand.
https://en.wikipedia.org/wiki/Hauser%27s_law#/media/File:U.S...
Total tax revenue in the US is 27% of GDP. In Sweden, it's 46%:
https://en.wikipedia.org/wiki/List_of_countries_by_tax_reven...