I love how this name change thing is revealing the shoddy lsl coding practices some people use. This is what happens when you have a bunch of cowboy coders and an API that doesn't enforce proper practices.
Every decent programmer has been using UUIDs even before name changes were announced. Because it makes sense. UUIDs are 36 characters, no more, no less, unlike usernames. UUIDs are designed for "identifying" things (it's in the name: Universally Unique Identifier), unlike usernames which were never guaranteed at any point to be static.