BTW: I've written 6 engines for AAA games. 3 of them used reference counting. AAA C++ games use garbage collection all the time. Maybe yours didn't. Mine did. Unreal does. So does Unity
That's like saying World of Warcarft uses garbage collection because it uses Lua. The higher level language on top of an engine isn't what was being talked about since Minecraft was written completely in Java and thus dealt with the garbage collector at every level.
BTW: I've written 6 engines for AAA games. 3 of them used reference counting. AAA C++ games use garbage collection all the time. Maybe yours didn't. Mine did. Unreal does. So does Unity