Why YSK: Because some people may want to use old reddit’s interface and might be used to it’s look. To choose the instance, put a /[instance name] after that url, or use the option given by the site itself
edit: apparently the original site where this came from is https://mlmym.org/ and this is the github repository https://github.com/rystaf/mlmym
Cool.
Alternatively you can install this userscript which, among other things, it also can change the Lemmy’s UI to something akin to old.reddit