Should I keep my older versions of UE4 installed? Is there a point or are they taking up space?

Just trying to get started on UE4 again. I have 4 versions of the launcher ranging from 4.13.2 to 4.21.2 ; is there any reason people keep their older versions?

It is up to you. If you have any third party plugins that no longer work on 4.21 you may need to use an older version. Or if something you really need is broken in 4.21 you may want to stay on an older version until it gets fixed. If you are just starting to learn the engine you don’t need the older versions.

also if trying to migrate projects to a newer version things do change / are removed in later versions which could break your project.