Yes, the hot-loading would do exactly what we wanted to do with ULX4 extensions. Good find!
Man, we could do a lot with that... Have a menu of available extensions maintained by us with tags, categories, usage statistics. This should be fun.

Also, I'm impressed they are removing some of the garry'isms and returning to how Lua was designed to work. This will simplify the dependency loading in ULX4.