I agree Lindsey, the list is arbitrary, and not everyone will, or will want to, accomplish these things by the time they are 30.
That said, I do feel you should try and accomplish as many of these as you can. There is no time like the present, and developing skills such as cooking and learning a new language will stand you in great stead for the remainder of your life.
I do feel it’s easy to get into bad habits in your 20s, that are hard to shake as you get older. However, as you rightly state, everyone goes at their own speed. History is full of late bloomers who have succeeded after 30. Maybe I should reconsider the title of the post!