MUI Layout Componentsに以下があるよ

• Box
• Container
• Grid
• Grid v2
• Stack
• ImageList
• Hidden(deprecated)

MUIの各ページから概要のみ抜粋したものです。以下でざっとそれぞれの用途がわかるかな。

Box

• The Box component is a generic, theme-aware container with access to CSS utilities from MUI System.

Container

• The container centers your content horizontally. It's the most basic layout element.

Grid

• The Material Design responsive layout grid adapts to screen size and orientation, ensuring consistency across layouts.
• 【初学者向け】React(TS) + MUIでGridを使ってレイアウトを作る
• 【React】Material-UIのGrid、Stackで横並びを実現する

Grid v2

• The responsive layout grid adapts to screen size and orientation, ensuring consistency across layouts.

import Grid from '@mui/material/Grid'; // Grid version 1
import Grid from '@mui/material/Unstable_Grid2'; // Grid version 2

Stack

• Stack is a container component for arranging elements vertically or horizontally.
• 【MUI】StackでFlexboxのgapが使えるようになった（実験的機能）

ImageList

• The Image List displays a collection of images in an organized grid.

Hidden deprecated ※じゃないか

• The Hidden component was deprecated in Material UI v5. To learn more, see the Hidden section of the migration docs.