This, I currently run triple 24inch monitors in portrait off my work 2019 16" laptop rather smoothly. Unfortunately the M1 couldn't run it. The new 14 and 16 max can do triple 4k.

Up to two external displays with up to 6K resolution at 60Hz at over a billion colors (M1 Pro) or Up to three external displays with up to 6K resolution and one external display with up to 4K resolution at 60Hz at over a billion colors (M1 Max)

When they make those statements I'm always curious if they are expecting the user to use two external with the lid closed, or open (which would be 3 displays).

I've always found MacBooks don't play well when the lid is closed, but maybe that has changed?

You could always get a big 4k display, install a window docking utility, and pretend that it's four 1080p monitors with no bezel.

MORE PANES!