This “solution” was actually buried in its original post. So here it is back to light.
Class added in Page Settings that is applied to a DIV with a paragraph custom class padding.
multicol.bloc (203.0 KB)
I have made the width to 1170px with a col-width at 20em. Then you can play with these to get what you desire. That said obviously worth for LG and MD breakpoints, while SM and XS especially would not make sense.
Would though be great to have this available directly in Blocs settings.