Considering when that was published, it obviously doesn't account for wide rims.
I don't know to what extent, or even if, that would affect things but I'd think if you do have wide rims, then that chart is conservative: ie you could run lower pressures.
Im running 28 gravelkings. They plush tyres for my 20mile commute.
Question i have for the forumites. What pressures should i run them at? Im currently riding them at 90psi i weigh ~69kg