Also the base 14" M3 only has one external monitor support vs two in in M3 Pro and 2 Thunderbolt 3/USB C port vs 3 Thunderbolt 4/USB C ports.
It gets even better with Apple steadfastly refusing to support MST well over a decade after its introduction so even if you have an M\d Pro or Max CPU many docks and chaining monitors will not work.
even on the order page https://www.apple.com/shop/buy-mac/macbook-pro