I'm sure we are all free to refer to any weight as ultralight we think works for us. For me, I think UL being under 10lb total is a standard I'm happy to use as a definition. So technically having a 9lb pack and everything else come in at 1lb would count, but I would struggle to describe a 9lb pack as UL. It shows the weakness of that definition for me. Moles definition when used in conjunction I think works better. But to my way if thinking an UL pack, to be UL should be appreciably lighter than a lightweight pack, which should be appreciably lighter than a pack, otherwise why the distinction? I think you can have an UL load with a 3lb pack, but the pack wouldn't be UL. The sub 2-300g packs I'd refer to as SUL. But I think we all do this for fun so whatever works for you is good. It's fun to see how light you can go, there is no harm in it, lots of us spend more time thinking about optimizing gear than using it.