We also use far less farmland than we did in the past, mostly due to the "green revolution" in the 1970s.

That's isn't true globally. For example, see here: https://www.ers.usda.gov/amber-waves/2024/september/global-c...

> Agricultural land area expanded 7.6 percent between 1961 and 2020 and currently occupies 32 percent of the world’s land area. Irrigated area more than doubled.