Create a Minecraft launcher to use old versions

In Java Edition, where a user can switch to for example, 1.9, 1.12.2, or 18w20a, whenever they want. I propose that this is implemented to Bedrock Edition as well, so old commands, for example, don’t have to be continually updated by the creator when a syntax change occurs that breaks the command! Also, this could be useful for creating texture packs, etc., so that newer blocks wouldn’t necessarily have to be in the game that the texture pack hasn’t created textures for.