That's a misleading term IMHO as that's what frame interpolation would be, upscaling 30 fps content to 60 fps content. An upscaler also doesn't need a temporal element although that obviously helps, adn can combine numerous analysis elements. If you had a motion element, tracking motion vectors, would you call it a "motion upscaler"? So really I think image reconstructors, with qualifiers for attributes used (temporal, spatial, motion, object, etc.)
Of course, what people actually use will probably be illogical and fairly arbitrary.
Just like every user/owner of a game these days is referred to as a 'fan'. "Good news for our fans - we're fixing the buggy mess you hate and wish you hadn't spent money on."